SSS: Exclusive to units considered arguably the best unit in the entire game. Currently only two ubers meet this criteria being both Lunos’.
SS: Top of the end game meta, only a few sets will even display this tier. Exclusive to ubers ranked within the top 10.
S: Extremely overpowered units who excel in their niche and general end game performance. Ubers that typically land around the top 30 are placed here.
A: Insanely powerful units who only suffer from minor blemishes. Shines above lower tiers either through surpassing generalist expectations or being particularly powerful at their niche.
B: Very strong units who are often used as powerful specialists.
C: Average units who are sufficient for their usage and offer a well balanced kit.
D: Slightly below average units who may struggle in a few of their designated departments. Typically have niche overlaps with a non uber unit or have generic roles.
E: Bad units who do not offer value through their niche, usually being outclassed by a handful of non uber options both in niche and generalist aspects. Only spared from F due to very small and situational scenarios.
F: Garbage units who have little to no use. Either completely outdone by non uber units or serve zero purpose to exist.
If you are going to share these tier lists without the context of this document, then you have failed to understand the importance of methodology in a ranking. As always, take every ranking with a grain of salt.