Mythic plus dungeons are one of the most popular forms of content in all of World of Warcraft. Offering some of the biggest challenges and greatest rewards, it's no wonder players flock to it.
One of the most controversial aspects of mythic plus's design is its affixes. Affixes are the modifiers placed on top of the dungeons to increase their level of difficulty. In the current iteration of mythic plus design, the tier 1 affix is active from +2 and up, the tier 2 affix is active from +5 and up, and the tier 3 affix is active from +10 and up.
If you want to check what the current affixes are at any given time or what the upcoming affixes are, you can do that here or directly on Wowhead.