Treat your effects that scale off of "players" or "opponents" as though there were one more. (For example, with myriad you'd make an additional token that's just attacking nobody, and with Braids, Arisen Nightmare, you'd draw an additional card.)
NM-Mint - $1.00
Lightly Played - $0.90
Moderately Played - $0.80
Heavily Played - $0.70
Damaged - $0.50
NM-Mint Non English - $1.00
Lightly Played Non English - $0.90
Moderately Played Non English - $0.80
Heavily Played Non English - $0.70
Damaged Non English - $0.50