Whenever a commander you control enters the battlefield or attacks, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
NM-Mint - $4.60
Lightly Played - $4.40
Moderately Played - $4.20
Heavily Played - $3.70
Damaged - $3.00
NM-Mint Non English - $4.60
Lightly Played Non English - $4.40
Moderately Played Non English - $4.20
Heavily Played Non English - $3.70
Damaged Non English - $3.00