Whenever an Aura or Equipment you control enters, create a 2/2 red Spirit creature token with menace.
At the beginning of your end step, put a +1/+1 counter on each modified creature you control. (Equipment, Auras you control, and counters are modifications.)
Chishiro turns every Aura and Equipment into a 2/2 menace Spirit, then snowballs the whole board with +1/+1 counters each end step. You flood the board with tokens, suit them up cheaply, and either go wide with an army of growing creatures or build a Voltron threat. Most games end by alpha-striking with an over-statted, hard-to-block board.
Generates immediate token value off cheap Auras and Equipment, building a board even without payoffs
Persistent end-step counter growth makes every modified creature snowball quickly
Menace tokens are evasive and stack well with anthems and trample
Operates well as a low-curve aggro deck that's resilient to single-target removal
Board wipes are devastating since the strategy commits many permanents
Heavy reliance on Chishiro being on the battlefield for token generation
Aura-heavy builds suffer card disadvantage to spot removal (two-for-ones)
Lacks built-in card draw and can run out of gas in grindy games