The Ultimate Warcraft Rumble Onyxia Guide (Deck, Phases, and Tips) – Updated 2024

How to Beat Onyxia in Warcraft Rumble

In this all-in-one Warcraft Rumble Onyxia guide, we’ll cover how to prepare, the best minis to level to get the lowest level kill, full phase-by-phase mechanics, and more!

At first, Onyxia is the final end-game boss fight that seems highly daunting at level 30. However, we have researched most of the given clears of Onyxia to date and bring you the most cost-efficient and lowest-level strategy to clear Onyxia, helping you to save your gold, XP, and cores.

By following our guide, you can defeat Onyxia 4-5 levels below her level!

We also have a step-by-step guide and a video illustrating how to take down the toughest boss in the game.

Post Bug Fix UPDATE

Onyxia was fixed with the introduction of Season 3 and Patch 4.0.0. These are a list of the undocumented changes observed so far:

• The bug where summoning too many units (usually whelp eggs) will cause Onyxia to stop summoning her own mobs has been fixed. This bug was the most exploited bug to clear Onyxia easily (but not used in our previous video clear).
• The bug where Whelp Eggs when knocked back into the river could be invulnerable in Phase 3, causing the Warders to infinitely get stuck hitting them, has been fixed.
• Whelp Eggs are no longer knocked back during her phase change deep breath and will now explode on the spot. Consequently, places to summon Whelp Eggs to prepare for the phase change deep breath has been changed (area behind your towers).
• In patch 3.0 released on 19 Dec 2023, Onyxia’s gold increase per phase increased from 0.05 to 0.1. This means that she summons much more accompanying units in each phase, and in Phase 3 her Warders will be accompanied by a lot of reinforcing troops, making it more difficult to hold off her attack and regain control of the map.

A much more difficult fight

With the fixing of the Onyxia bugs and boost to her gold regeneration, she is now a much tougher boss to defeat. All 5+ underlevel recorded clears of Onyxia were done using either exploit, mostly the unit cap bug, which essentially reduced the fight difficulty 10x.

Luckily, if you did not exploit that bug and trained on Onyxia fight the standard way, you will notice the fight is not much different and can still be cleared with an underleveled Rend team post-fix.

Changes to the team

As Whelp Eggs are nerfed both in their placement and the bug fix and the Warders are not being delayed by them anymore, they start being a deadweight in the team which is only useful for sniping Necromancers, and even then, not always successfully.

We drop Whelp Eggs for Pyromancer, which provides an amazing method to snipe off Necromancers, Drakes, and Grphyon Riders. There are a few reasons why she is so good and best suited for this fight compared to any other minis:

• Largest AoE – With her Conflagrate talent which doubles her splash area, she can cleave a lot of minis behind her target. One of her best-use scenarios is after the tower is taken over during the Deep Breath phase change. Pyromancer can continuously hit the enemy tower safely while it is still building and splash any summoned enemy Drakes or Necromancers which are passing by the tower. No other minis can do this – Whelps, Drakes, and Rend would all usually get killed by one level 30 drake if you were unlucky. Pyromancer can also be played when she summons Gargyole and Earth Elementals, and continuously use them as a focus point for her to splash and kill all minis alongside them. Most importantly, she clears all minis summoned alongside Warders in Phase 3, something that the Rend team often struggled with with slow-moving minis which all die to Drakes or Necromancers.
• Cheap – At 3 cost, she is the cheapest ranged mini that can deal with all the flyers minis. Ogre Magi and Huntress are too expensive in a deck that you want to consistently cycle to get more meat wagons to damage Onyxia.
• Slow movespeed – Unlike Huntress or Harpies, you want Pyromancer to move as slowly as possible, giving her more time ‘on field’ before she walks to the end of the map into the Onyxia meat grinder. That extra few seconds of time she takes to walk from your last tower to Onyxia’s face can mean the difference between catching a new Drake spawn from Onyxia and killing it versus dying without doing any extra damage.

It is no exaggeration to say that Pyromancer is now the MVP of the Rend team. This deck only took 3 attempts to clear the new buffed Onyxia, with all 3 attempts easily making it to Phase 3 versus the old Whelp Eggs deck which was more inconsistent.

Controlling how, when and where you place her and use her is the most important factor in clearing Onyxia as she is your key mini for recapturing Towers during phase changes and in Phase 3, where she will be solo clearing large groups of minis as long as there is a tank in front of her.

The rest of the fight is pretty similar to the fight outline in the guide below, apart from summoning whelps to prepare for phase change, you should instead be holding Pyromancers when Onyxia is about to hit 66% and 33% hp, so that you can have a Pyromancer ready to take back your towers by splashing all enemies around the tower.

Onyxia’s Army Composition

• Whelp Eggs
• Gargoyle
• Gryphon Rider
• Necromancer
• Skeletons
• Drake
• Spiderlings
• Earth Elemental
• Warsong Grunts
• Dragonspawn Warders (shown below)

Onyxia’s army predominantly deals elemental damage. These include the Whelp Eggs, Necromancer, and, Drake, as well as Onyxia herself. Onyxia’s army also boasts a high number of flying units in the form of Whelp Eggs, Drakes and Gryphon Rider.

The Best Leader and Minis For Beating Onyxia

• Leader
  • Rend Blackhand
• Minis
  • Drake
  • Whelp Eggs
  • Harpies
  • Defias Bandits
  • Quilboar
  • Meat Wagon

Rend Blackhand

Rend Blackhand is the best leader for taking down Onyxia due to the high number of Whelp Eggs summoned periodically by Onyxia, as well as his cost reduction for flying minis.

Since the Onyxia fight can last for up to 8 minutes, Rend can generate so much value by being on the field and constantly playing other flying units at a cheaper cost. His talent Scale and Steel also grants him resistant while on his Drake, allowing him to survive longer and kill the enemy’s Drake and Necromancer.

He also flies really slowly, which is a very important thing in the Onyxia fight as it allows him to stay within range of your towers for a longer period of time as she will constantly summon both Whelps Eggs and Earth Elemental to assault your towers. He also deals elemental damage whilst in the air, and is thus able to kill her armored Earth Elementals and Gargoyles quickly.

Drake

Drake is used for the same reasons as Rend, being a great pick against the massive number of Whelps Eggs and Earth Elemental summoned. As there are two lanes with Whelps Eggs and Earth Elemental that you have to clear constantly, you will want to drop Rend on the left lane and Drake on the right lane to ensure both lanes are always cleared of her reinforcements.

Its Mother Drake talent which summons Whelps Eggs periodically is technically the stronger talent for Drake as allows any enemy grunts and spiders who slip through your defences to be delayed by the whelps, and just generally delay a lot of their minions as they hit her eggs, including the Warders on Phase 3 who wastes a lot of time hitting the eggs minefield.

However, your Drake will not be able to trade equally with the enemy’s level 30 Drake in a 1 v 1 matchup, and will die leaving their Drake with a sliver of health left, which will require you to either to use a Quillboar tank in conjunction to distract their Drake for your Drake to finish it off first.  I personally prefer Engulfing Flames as my talent pick, which will allow you to kill their Drake in a single attack due to the additional burning damage, and deal with the Earth Elementals much quickly.

Whelp Eggs

Whelp Eggs is another flying unit that is discounted with Rend. However, its true value lies in its hatching mechanic, which activates on its death. Onyxia fight has 3 Phases.

During the Phase transition from Phase 1 into Phase 2, and Phase 2 into Phase 3, Onyxia will do a breath attack which immediately kills all of your troops and the 2 front towers nearest to her, converting the towers to her side again.

However, if you drop Whelp Eggs in preparation for her phase change, the Whelps Eggs will die to Onyxia’s Execute, spawning Whelplings who will immediately take back the tower as it is converting to Onyxia’s side. This will save you a ton of time by helping you recapture the towers immediately, allowing you to get back to using Meat Wagon on Onyxia.

Whelp Eggs can also be used to delay Grunts and snipe Necromancer, though Whelps can only completely kill Necromancer from hatching with Flame Break at level 26. At level 24, the Whelps would have to get in a few attacks on Necromancer, which may not always happen as they may be distracted by his skeletons.

Harpies

Harpies is yet another flying unit that works with Rend’s reduced cost. Harpies is the only fast unit in this deck and can be used to quickly take towers and defend your towers.

Since they only hit enemies in melee range, they are useless against Onyxia who will kill them before they can even get close. They are thus only meant to be used reactively as a cheap 2-cost mini, to quickly kill units that are assaulting your towers or are going to reach your Meat Wagons.

Defias Bandits

The Onyxia map has 2 chests close to your towers. Defias Bandits can thus easily provide a costant stream of +3 gold with the Pick Lock talent. He also helps out in defending your towers against the Earth Elementals she summons in Phase 2, and playing him constantly will help you cycle back to your other key units like Meat Wagon.

Quilboar

Quilboar is the best tank for this map due to his resistant trait, which allows him to take 50% less damage from elemental attacks. This is highly useful as a majority of units in Onyxia’s fight deals elemental damage, including Onyxia herself.

Being unbound further allows him to be placed in between Onyxia and Meat Wagon at any time to distract any minis summoned by her, ensuring that the Meat Wagons survive as long as possible.

Lastly, he is also key to distracting the Warders in Phase 3 of her fight, which is widely regarded as the most difficult part of the Onyxia fight.

He is preferred over Earth Elemental due to his lower cost yet equal tankiness due to his resistant trait, but Earth Elemental can also take this slot, which has the added advantage of making it much easier to capture towers, at the cost of having a more difficult Phase 3 against the Warders.

Meat Wagon

Meat Wagon is the core to the entire low level Onyxia clear strategy. With the Filet Trebuchet talent which increases her range by 2, Meat Wagon is the only mini that can that can hit Onyxia without being in her range. The entire Onyxia fight thus becomes a fight to protect the Meat Wagon while it slowly sieges her down from afar.

Leveling Priority

In terms of levels, your entire team should be at least 24 to even start attempting Onyxia, otherwise, you will not meet the damage required to take her down.

In general, upgrading any of these minions would lead to faster clear times as all your units will trade better and defeat their minis faster, clearing the way for more Meat Wagon uptime, and of course, having a higher level base and tower will make defending with them easier with higher hp and damage per shot.

However, some minis will help you improve your time more than others, and some are more essential to getting past the most difficult Phase 3. Having tested the fight many times with level 24 minis then progressively leveling them, these are in my opinion the most impactful minis to level in order:

• Quilboar
• Rend Blackhand
• Meat Wagon
• Drake
• Whelp Eggs
• Harpies
• Defias Bandits

Quilboar

You may be surprised to find that Quilboar takes the top spot. The reason is that with a team of level 24s, you technically have the damage required to clear Onyxia in the 8 minutes you are given. However, the most difficult obstacle you will face is passing Phase 3, and all of that difficulty boils down to taking down the 2 Warders as fast as possible without losing too many units and towers. Quilboar helps the most with that part, as will be explained in the detailed Onyxia guide.

Rend Blackhand

Rend is the next priority for similar reasons. Leveling him up makes him survive longer and trades better with their Necromancer and Drake, especially since he has the resistant from his talent as well. More importantly, spamming Rend on the left lane is also a key way to handle the Warders in Phase 3, which will be covered in the fight breakdown. Apart from that, he will take down the beefy Grunts, Gargyole, and Earth Elementals faster.

Meat Wagon

Meat Wagon is leveled so you have more time on the clock to defeat Onyxia. More levels means higher damage per shot, so if you are struggling with the time limit, Meat Wagon would allow you to make more mistakes throughout the fight and still have time to recover.

Drake

Drake levels will help you trade with the enemy Drake better and take down the numerous Grunts, Gargyole, and Earth Elementals faster.

Whelp Eggs

Whelp Eggs can technically be underleveled as their main purpose is to take back the towers when Onyxia does her phase change, and you can easily use spam more of them on the field to make up for the lower leveled whelps. Do note that under level 24, the level 30 Necromancers get harder to snipe with purely Whelp Eggs alone, and you may need other backup to clear the Necromancer away.

Harpies

Harpies are not essential to any trades and are there to whittle down the targets that mainly don’t hit back like Grunts, Gargoyles, and Earth Elementals. An extra level or two does not dramatically change their performance apart from taking an extra hit to kill their target.

Defias Bandits

Defias Bandits are just there to open chests, so their level barely matters. A low-level Bandit does mean that their stun lasts shorter vs the Earth Elementals, though that is hardly impactful.

Should I rush to kill Onyxia?

My advice is – if you are at or close to the recommended level of level 25- 26 for the above minis, do it as soon as possible instead of waiting for a long time to overlevel it.

The reason behind this is somewhat controversial – Onyxia is currently plagued with bugs that make the fight easier than expected. Further, there may be nerfs to certain units in this popular Rend composition that may be deemed too strong, making future attempts on her more difficult.

Although this may be controversial, it is a matter of journalistic integrity to not withhold information that gives you a full picture of the state of the “endgame” fight of Rumble.

Balance Changes and Bugs

To quote a few examples from Rumble’s patch notes which you can find in this link.

On October 17, 2023, update 2.0.0 made the following changes to Onyxia (Rumble was already live and in soft release for many countries):

This was a significant change if you read the detailed fight for Onyxia below. The fact that Onyxia did not destroy your towers is a major mechanic change that can easily save you nearly 1 minute out of an 8 minute fight.

Players who cleared this fight before these changes experienced an easier version of this fight and the clear was not taken away from these players who cleared Onyxia before these changes.

Another change to Onyxia’s difficulty happened indirectly on Update 2.1.0

Though not immediately apparent, both these particular heroes were nerfed, presumably as  Thalnos and Sneed were infinitely scaling heroes.

This meant in a long fight like Onyxia, they could potentially gain a lot of levels if you delayed their advance enough for yourself to stack their levels. There are YouTube videos showing this in action showing clears of Onyxia with obscenely low levels, with plenty of spare time left on the clock.

This also meant that players who had thought or learned of this strategy and who were actively working towards and probably spent some money getting there were locked out of their chance to utilize this strategy, wasting their resources, time, and potentially money.

There are currently a few active bugs in the Onyxia fight still, one of which is addressed in the linked YouTube video.

There is currently another exploit that isn’t obvious, but if you look through YouTube you’ll find the other bug is used for many clears.

In short, the current most well-adopted low-level clear strategy, being Rend’s deck, may be nerfed in the future, or some components of his deck may be nerfed, or current bugs that affect Onyxia are fixed. If you have the resources to clear Onyxia now, there’s no better time than the present to get your attempts in.

Warcraft Rumble Onyxia Fight Breakdown

With all the preparation work done, we now move on to the actual Onyxia fight. You may watch a video of my first Onyxia victory here, for reference for the strategies I will go through in detail below.

A general tip for slower players who are really bad at multitasking (like myself, as evident from the video), is that you can pause the match at any time and observe the battlefield.

There will be a lot of things happening at once, with pushes coming from 4 locations, 4 towers to defend, 4 gold mines to capitalize from, and 2 chests to constantly open.

Don’t be afraid to use that pause button to observe the battlefield – I’ve lost too many close clears where I did not notice an Earth Elemental sneaking up to my base!

Phase 1

Whelp Eggs Swarm

Onyxia will periodically summon Whelps Eggs in the left and right lanes in the above manner. The eggs first spawn 20 seconds into the fight, and will continuously spawn approximately every 90 seconds after (i.e when there is 5:40, 4:10,  2:40, and 1:10 left on the clock).

The eggs will stay dormant for around 30 seconds, before they will hatch and start flying towards your home base. It is recommended you deal with the eggs when they are still dormant by constantly summoning Rend and Drake in each lane from the bottom of the map, or you can time it according to the timing above. Their slow movement speed will usually ensure that one of them is passing by the eggs whenever she resummons them.

Opening Push

As every player’s hand is different from each other (but fixed for each player until you clear Onyxia), the opening attack for each player will look different for everyone even if they have the same deck.

You will have to devise your own opening that is as resource efficient as possible, but accomplishes the following things. Don’t be afraid to experiment! Even 50 tries in I was finding out for efficient ways to make my first push.

1. Use Bandits to open the nearest chest. If Bandit is not in your opening hand, use your other units until you get Bandits in your hand.
2. Play Rend to deal with the initial push or to tank the middle tower. Once dismounted, Rend has Armored, which serves as a good tank for the towers.
3. Harpies can support Rend in the initial push to quickly get down a tower. (Note: Meat Wagon is not used even though he outranges the tower, because he will start randomly firing at the Whelp Eggs and breaking them).
4. Drop a Drake on the right lane to deal with the eggs.
5. Summon your kobold in the right lane to mine as he is protected by your Drake.
6. Quilboar and Whelp Eggs can be used to tank the left tower and kill any summoned defences as your Harpies approach it.
7. By this time, you would have cycled through to get either the Drake or Rend again. Drop either of them in the left lane before the eggs hatch.
8. Drop a Kobold in the left lane protected by Rend
9. Once your left tower converts to your side, drop a Meat Wagon to start sieging Onyxia.
10. Remember to use Bandit to open the base chest again, as it would have respawned around now.
11. Meanwhile, your drake from the right side should be approaching the left tower. Use whatever units you have on hand to support it and take the right tower down.

Once you have captured all 3 towers, it is time to start poking Onyxia to death.

Maintaining the Siege, Set up for Phase 2

For the rest of Phase 1 (and the rest of the fight), you will have to keep up the following steps:

1. Summoning Bandits to open chests
2. Kobold on the right and left lanes in turns to keep mining
3. Summon Rend and Drake on the bottom right and left lanes.

At the same time, on the front two towers, drop Meat Wagons to constantly hit Onyxia. You can either drop one on each side or both on the same tower. I prefer dropping one on each side to minimize losses.

Try to use Quilboar to distract the enemies away from the rest of your troops, especially Drakes, who can wipe out most of your units and deal significant damage to your towers.

Onyxia starts Phase 2 once her health drops to 2/3. Before that, you will have to set up some Whelp Eggs in preparation for the phase change, so that your eggs will hatch and recapture your towers. Drop 2 sets of eggs, one on the left and right of the chest.

Phase 2

Earth Elementals Assault

Onyxia knocks your units back and does an AoE breath attack (3:25 into the video) which kills all your units and towers, then summons 4 Earth Elementals in the spots seen in the image.

Like the Whelp Eggs, Onyxia will continuously summon the Elementals as well, in addition to her eggs. Luckily, Rend and Drake are well suited to counter both Earth Elementals and Whelp Eggs, so the general strategy of dropping Rend + Drake at the back continues to be effective.

Apart from the additional Earth Elementals, nothing too drastic changes, other than the added burden of having to deal with the two elementals being constantly summoned and attacking your top two towers. This is where Harpies come in especially handy, being able to quickly kill the Elementals for 2 mana.

You should summon the Harpies to the right of the summoning area so they can move toward the right tower after cleaning up the Earth Elemental.

Setting up for Phase 3

Like before, you will want to start positioning your Whelp Eggs around the chest. In addition to that, you will want to start summoning Rend solely on the left side of the map, and Drake on the right side. You will want your Rend to start stacking up and ideally hit the change to Phase 3 while you have a few Rends at the area around your tower.

Phase 3

Dragonspawn Warders

Finally, the greatest challenge of all Onyxia comes in the form of two Dragonspawn Warders. Think of them as units with the bulk of a Molten Giant, but with the attack of a Pyromancer that hits both land and air…and there are two of them.

Ideally, you should be transitioning to Phase 3 just as your timer nears 0:00, as this indicates that you are going into overtime (an extra 2 minutes) which will grant you 2x the gold income, which you will sorely need to deal with the Warders. Your strategy is to burst them down one by one. The left Warder is easier to reach due to his proximity to your middle tower.

Your general strategy is as follows:

1. Your Whelp Eggs would have hatched from the phase change and are taking back the tower

2. Your Rends are slowly making their way over to the left tower help take it back, then continue pushing on to engage the Warder.

3. Drop Quilboar to tank the Warder away from your main troops. This is to buy time for your troops to take over the tower, and to delay the Warder long enough for the tower to convert back to your side.

4. Hopefully, one of your Rend also reaches the Warder and starts taking over the tanking and damage once your Quilboar goes down.

5. Once the tower converts back to your side, either let the Warder target the tower first so that the tower tanks his shots, or cycle back to Quilboar and do another backward tank, then unload all your units on him from the tower you just recaptured. Harpies and Meat Wagon deal the most damage to the Warder as he is resistant and will take less elemental damage from Drakes and Rend.

6. While doing this, do be aware that Onyxia is still constantly summoning Whelp Eggs, Earth Elementals, and other normal minions in other lanes. This may be a good time to pause to evaluate how much resources you should commit to try and take down the left Warder, because you still have to deal with the right Warder and your lanes.

7. After you get the left Warder down, the right Warder should be hitting your middle tower or already approaching your base. Attempt to take him down using the same strategy of Quilboar tanking or letting him hit the tower first, then unloading harpies and your units on him.

8. Do note that stunning the Warder will cause him to reset his aggro, so if for example he is already hitting your tower and you drop Harpies + and Bandits, the Bandits will stun the Warder, causing him to retarget the Harpies. Therefore please use your Bandits sparingly on the Warder.

If you don’t succeed, don’t be discouraged! Taking them down is a matter of luck as you cannot always control when Onyxia is going to change phase (as near to overtime as possible but not too far in or you will run out of time) or the resources she currently has.

If she changes phases while sending out a couple of Necromancers and Grunt guarding the Warders, you are unlikely to be able to hold them off. After all, we are attempting a <4 – 5 levels clear of the toughest boss in game, and resets are bound to be necessary.

Once you have both Warders down, you’re in the home stretch! Throw everything you have at Onyxia with all your resources including your Whelp Eggs in her face and try to burst her down before the time runs out.

In conclusion

Congratulations for making it to the end of our Warcraft Rumble Onyxia guide, and hopefully you will make it to the end of the fight as well.

Note that there are few other decks that are currently used to defeat Onyxia, which aims to exploit another bug to defeat Onyxia. However, the other bug, if fixed, completely destroys that strategy, leading to a very wasted of investment.

The Whelp Egg bug covered in the Youtube video, even if fixed, does not change the fight much, and you will continue to use the same strategy employed here, but you would have to be much luckier with your runs to get a good run with a good Warders deployment.