Whenever a player casts an artifact, instant, or sorcery spell, you create a Mutagen token. (It's an artifact with "{1}, {T}, Sacrifice this token: Put a +1/+1 counter on target creature. Activate only as a sorcery.")
If you steal mutagen that doesn't exist from aliens that also don't exist, it's not really theft. More like creative writing!
Near Mint - $2.30
Lightly Played - $1.80
Moderately Played - $1.60
Heavily Played - $1.40
Damaged - $1.20
Near Mint Spanish - $2.30
Lightly Played Spanish - $1.80
Moderately Played Spanish - $1.60
Heavily Played Spanish - $1.40
Damaged Spanish - $1.20
Foil Prices
Near Mint Foil - $0.10
Lightly Played Foil - $0.10
Moderately Played Foil - $0.10
Heavily Played Foil - $0.10
Damaged Foil - $0.10
Near Mint Foil Spanish - $0.10
Lightly Played Foil Spanish - $0.10
Moderately Played Foil Spanish - $0.10
Heavily Played Foil Spanish - $0.10
Damaged Foil Spanish - $0.10