As Six-y Beast enters the battlefield, you secretly put six or fewer +1/+1 counters on it, then an opponent guesses the number of counters. If that player guesses right, sacrifice Six-y Beast after it enters the battlefield.
NM-Mint - $0.50
Lightly Played - $0.45
Moderately Played - $0.40
Heavily Played - $0.35
Damaged - $0.25
NM-Mint Non English - $0.50
Lightly Played Non English - $0.45
Moderately Played Non English - $0.40
Heavily Played Non English - $0.35
Damaged Non English - $0.25