Affixes

Mythic+ affixes are special modifiers that increase the difficulty of dungeons. They introduce additional mechanics that must be dealt with, and also strengthen bosses and mobs.

There are 7 types of modifiers in total: 4 Xal'atath's Bargain modifiers (Devour, Void Bonds, Pulsar, and Ascendant) that activate at key level 4; 2 modifiers that increase the difficulty of bosses and mobs (Fortified and Tyrannical) that activate at key levels 7 and 10; and the Treachery of Xal'atath modifier that activates at key level 12.

Affixes change weekly, every Wednesday at 04:00 AM. The affix for level 4 keys is replaced with the next one in the cycle, the affixes for level 7 and 10 keys swap places with each other, and the level 12 key affix is always fixed.

No. Affixes always appear on your key once you reach a certain level (4, 7, 10, 12), and they cannot be disabled or swapped for any other modifier.

No, affixes do not affect what rewards you receive. However, the key level you complete does affect rewards: the higher the key level, the better the rewards you can get at the end of the dungeon.

Yes, affixes directly affect the challenges you will face inside the dungeon. For example: mobs affected by the Fortified modifier will deal more damage; bosses affected by the Tyrannical modifier will take longer to defeat, which means you'll have to deal with more mechanics.