Skills are divided into Passive, Active, and Ultimate types, and each is subdivided into N, R, and SR grades.
The avatar has a total of 4 skill slots, and only skills divided into categories for each slot can be randomly assigned. 5 $META allows you to randomly change all 4 slots to 1st level skills.
Each skill is subdivided into rarity of N, R, and SR, and the higher the rarity, the more superior abilities such as additional effects.
For example, Taunt (N) only has the effect of making the enemy attack you, but Taunt (SR) adds a damage reflection effect and an option to reduce the enemy's attack power to the basic effect.
You can raise the skill level through Fusion > Enhance Skills. In the case of the same skill, the skill points of the sacrifice avatar are accumulated in the skill points of the base avatar.
The level is determined according to the accumulated skill points, and the rank does not change as the level rises.