Druid
OracleWyvern Druid is a build with amazing map clear and bossing. It's extremely easy to play, it's simple to gear, and it has pretty strong passive defensive bonuses due to Wyvern Form.
You cast 
Pounce to move between packs of enemies, and you kill them with 
Rend.
Because Rend is a basic attack, you don't have any mana concerns and keeping it leveled up and socketed throughout the campaign and endgame is trivial.
Your primary source of boss damage is 
Oil Barrage, which deals massive amounts of single-target damage to bosses when empowered by consuming Power Charges.
Campaign Notes
Upgrade your talisman to keep your damage up throughout the campaign. Try to get as much life and elemental resistance as possible on your gear to help with survival.
Life Leech is a useful stat on rings or gloves for helping with sustain.
Wyvern Form is not unlocked until level 6, so you will have to play Wolf or Bear as your shapeshift form through level 5. Playing Wolf and using 
Shred and 
Lunar Assault works very well for the opening of Act 1.
Power Charges
Generating and consuming Power Charges is the core of this build. 
Wing Blast helps with charge generation on bosses throughout the campaign and early endgame, and 
Devour generates charges and restores health while clearing.
Once at endgame, linking Ailith's Chimes onto Pounce will solve all Power Charge generation issues. Attack a few times with Rend, then cast Pounce, and you will have charges!
In terms of spending Power Charges, both of your main skills use them. Casting Rend will consume a Power Charge to grant a 10-second buff that gives Rend increased range and damage (it will not consume charges if you already have the buff active).
If you have Power Charges active, Oil Barrage changes from a simple setup skill to a massive barrage of damage that can be continuously channeled onto bosses for as long as you have power charges available.
You have a third, optional skill available in 
Flame Breath, which consumes both Rage and Power Charges to last longer. It deals a lot of damage, but can be a little clumsy to use.
Gem Priority
Here is your priority for leveling and adding support gems to your primary skills.
- Oil Barrage
- Rend (support gems only)
- Flame Breath
- Pounce
- Devour
- Wing Blast
Freezing Mark (crafting this gem requires having a bow equipped)
Herald of Ice
Eternal Rage
Act Bonuses:
- Act 2: Charm Charges Gained
- Act 3: Stun Threshold
- Act 4: Life Flask
- Act 4: +5 Resistances
- Intermissions: Resistances/Speed
