Keepers of the Flame: Content Livestream Summary
Overview
Keepers of the Flame League Mechanic
The Keepers of the Flame league mechanic is essentially modernising the Breach mechanic in Path of Exile, bringing it up to the current quality bar of more recent releases, and utilising assets from the newer Path of Exile 2.

Horrors await in the Breachlord's domain
You can check out our full article on the new Keepers of the Flame league mechanic which goes into more detail, but the 3.27 update will help to diversify the encounters offered by the Breach mechanic in areas, providing more than just 'kill monsters in a circle'. But fear not, the simplicity and appeal of Breach is not going away in Keepers of the Flame - quite the opposite in fact! Breach encounters will often contain a large hand that, you guessed it, spawns an expanding circle flooded with Breach monsters - perfect!
New Skills & Support Gems
Path of Exile 3.27 will introduce the first entirely new skill gems to the game since the ARPG committed to transfigured gems back in patch 3.23. The transfigured gem system enables some interesting developments beyond the current skill archetype options, but it's ultimately limited by the core skill.
Instead of introducing new transfigured skill options in Keepers of the Flame, Grinding Gear Games are implementing new Wand and Bow skills and support gems to bolster the ranged-attack archetypes, a playstyle that has been lacking of late.

The new Kinetic Rain skill in action
There's several new skill and support gems options available in Path of Exile: Keepers of the Flame, with some mechanics that are more focused on map clear, and others that excel at bossing, making them a bit more versatile for potential new build options too!
Bloodline Classes
Bloodline Classes are brand new ascendancy options that can be enabled alongside your core ascendancy in Path of Exile: Keepers of the Flame, essentially allowing multi-classing. These new classes are somewhat similar to the Wildwood ascendancies of old, but their mechanics are quite different.

The Harvest Bloodline
Bloodline Classes function identically to a typical ascendancy tree, allowing points to be spent to obtain powerful modifiers from Notables and their proceeding smaller nodes. However, it should be noted that your base ascendancy class will share ascendancy points, obtained from labyrinth ascension, with your chosen Bloodline Class. That means you'll have a maximum total of 8 points combined to spend on your base ascendancy class and your Bloodline Class.

Aul, the Crystal King
Bloodline Classes are first encountered in the endgame, and access to a Bloodline Class can only be obtained by defeating an endgame boss and interacting with the class mechanic in the arena thereafter.
Asynchronous Trade
After if first appeared in Path of Exile 2, fully asynchronous trade is now making its way to the original game in the Keepers of the Flame update. You can now make use of special tabs to list your for-sale items at your ideal price. A buyer can then find your items via trade search, either traditionally on the website or by utilising the new in-game trade browser feature.

Listing an item for sale
Once a buyer has found your item, they can travel to your hideout at the click of a button and finish the trade without requiring your presence - no need to exit a map, and you can even make sales while you sleep! Simply talk to Faustus to obtain your end of the deal, minus some gold for old Faustus' lunch money, can't have him going hungry now!
Uber Incarnation Bosses
New Incarnation pinnacle bosses were added to Path of Exile in the 3.26 update: Secrets of the Atlas. Now, just one patch later, the much scarier Uber version of these bosses will be unleashed upon Wraeclast. The new bosses include more difficult versions of the Incarnation of Dread, Fear and Neglect.

The Uber Incarnation of Neglect
The Uber versions of these bosses will have new mechanics, much more threatening levels of damage, and perhaps most importantly, new loot to find!
Just like the currently accessible Uber boss fights in Path of Exile, you'll need to venture into Tier 17 maps and defeat the bosses that reside there in order to obtain fragments to access these new bosses.
Quality of Life Improvements
There are more then dozen quality of life improvements being added to Path of Exile in 3.27, including the ability to respec your entire character Passive Skill Tree or Atlas Passive Tree in a single click, and being able to identify all items in your inventory in a single click at a vendor, without the need for any Identification Scrolls.

Fully refund with a single click
New Supporter Packs
As is tradition, there's a new set of supporter packs to empower the future development of Path of Exile and Path of Exile 2, which you can find more information about here.

Verdant Magus Supporter