If Looks Could Kill

As this creature enters, choose a creature type. This creature is the chosen type in addition to its other types. Other creatures you control of the chosen type get +1/+1.

Tap an untapped Wizard you control: Draw a card.

+1: Search your library for a Swamp card, reveal it, put it into your hand, then shuffle. −3: Target creature gets +X/+X or -X/-X until end of turn, where X is the number of Swamps you control. −6: You get an emblem with "Swamps you control have '{T}: Add {B}{B}{B}{B}.'"

When this creature enters, return target creature an opponent controls to its owner's hand. That creature's owner can't cast spells with the same name as that creature until your next turn.

All Slivers have "Sacrifice this permanent: Add {B}{B}."

Sliver creatures you control have menace. (They can't be blocked except by two or more creatures.)

All Slivers have "{T}: Target Sliver creature gets +X/+0 until end of turn, where X is the number of Slivers on the battlefield."

All Sliver creatures get +1/+1.

All Slivers have "Whenever this permanent becomes the target of a spell an opponent controls, you may draw a card."

All Sliver creatures have flying.