Thoughtseize

Target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.

Rat Colony

Rat Colony gets +1/+0 for each other Rat you control.
A deck can have any number of cards named Rat Colony.

Fatal Push

Destroy target creature if it has mana value 2 or less.
Revolt — Destroy that creature if it has mana value 4 or less instead if a permanent you controlled left the battlefield this turn.

Extirpate

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Choose target card in a graveyard other than a basic land card. Search its owner's graveyard, hand, and library for all cards with the same name as that card and exile them. Then that player shuffles.

Dash Hopes

When you cast this spell, any player may pay 5 life. If a player does, counter Dash Hopes.
Counter target spell.

Necromentia

Choose a card name other than a basic land card name. Search target opponent's graveyard, hand, and library for any number of cards with that name and exile them. That player shuffles, then creates a 2/2 black Zombie creature token for each card exiled from their hand this way.