A Tier refers to the group in which an NPC belongs under, depending on its statistics. Tiers aid the player in figuring out how powerful an enemy is and how difficult it will be to combat and defeat. An NPCs tier is determined by their health, attack, and defense. An NPCs tier is indicated by an icon next to their nametag, and the tier name under their name when targeted (except if the NPC is in the "Average" tier, in this case nothing shows).
The Weak tier is the lowest tier that an NPC can have. Normally having low health, attack, and defense, weak NPCs normally have basic abilities, and are often easy to beat. Weak enemies, unless boosted by their abilities, almost never have any buffs. Weak enemies are also typically seen as cannon fodder or for swarming reasons. Weak NPCs are also prone to being knocked down.
The Average tier is what a majority of NPCs belong under. Average NPCs normally have moderate health, low attack, and little to no defense. Most friendly and hostile NPCs will belong under this tier. Enemies under this tier will also have basic abilities, along with having appropriate buffs applied by their abilities or NPCs around them. Like weak NPCs, Average NPCs can be knocked down by abilities that cause this.
The Average tier is also distinguishable due to the fact that it does not display an icon.
The Strong tier is another common tier that NPCs may belong under. Strong NPCs typically have moderate health, attack, and defense, and can pose a threat to under-equipped players. Enemies under this tear are prone to using abilities and buffs more than any previous tier. Unlike Average and Weak, Strong NPCs are typically unaffected by basic knockdown abilities.
NPCs in this tier typically have moderate health, high attack, and partial to half defense. A lot, if not all, Guardian characters are found in this tier.
NPCs in this tier typically have very high health, high to very high attack, and no to full defense. Most Boss characters are found in this tier.
NPCs in this tier typically have very high health, very high attack, and partial to full defense. Mightier, end level Bosses are usually found in this tier.
NPCs in this tier typically have very high to extremely high health, very high to extremely high attack, and partial to full defense. A lot of Chamber bosses and some End bosses are found in this tier. NPCs in this tier are uncommon.
NPCs in this tier have extremely high health, extremely high attack, and full defense. This is the rarest tier to see, and NPCs found in this tier are very rare to encounter.