The Mindskinner can't be blocked. If a source you control would deal damage to an opponent, prevent that damage and each opponent mills that many cards.

Flash Enchant creature Enchanted creature gets -2/-0 and loses all abilities. (Mutating onto the creature won't give it new abilities. It can gain abilities in other ways.)

When Mjölnir enters, attach it to target legendary creature you control. Whenever equipped creature attacks, tap target creature defending player controls and put a stun counter on it. Then Mjölnir deals damage to each opponent equal to the number of tapped creatures that opponent controls. Equip {4}

Enchant creature You control enchanted creature. Enchanted creature gets -3/-0 and loses all abilities.

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.) Equip {0}

Equipped creature gets +2/+2 and has protection from black and from green. Whenever equipped creature deals combat damage to a player, that player discards a card and you untap all lands you control. Equip {2}