For his assist, Yatterman-1 will use his medium Kendamagic. This is arguably one of the most useless assists in the game. It rarely works when it's needed and it's very hard to get it to be of use in combos. Using it as a projectile suppliment is also difficult due to the precise nature of the attack.
Variable Hyper Combination
When joining in a Variable Hyper Combination, Yatterman-1 will use the Yatterwan Special Attack hyper.