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 - $6.00
Lightly Played - $5.70
Moderately Played - $5.40
Heavily Played - $4.80
Damaged - $3.90
NM-Mint Non English - $6.00
Lightly Played Non English - $5.70
Moderately Played Non English - $5.40
Heavily Played Non English - $4.80
Damaged Non English - $3.90