Buy @ TCGplayer
At the beginning of combat on your turn, create a green Aura enchantment token named Settlement attached to up to one target land you control. It has enchant land and "Enchanted land has '{T}: Add one mana of any color.'"
Whenever Preston Garvey attacks, untap each enchanted permanent you control.
If the target land is an illegal target as Preston Garvey's first ability tries to resolve, it won't resolve and none of its effects happen. The Settlement token won't be created.
In the rare case that the target land is a legal target as Preston Garvey's first ability resolves but the target land can't legally be enchanted by the Settlement token, the token won't be created at all.
