Graf Rats

At the beginning of combat on your turn, if you both own and control this creature and a creature named Midnight Scavengers, exile them, then meld them into Chittering Host.
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Meld Partner: Midnight Scavengers

When Melded, it becomes the following:

Chittering Host

Creature — Eldrazi Horror
Haste
Menace (This creature can't be blocked except by two or more creatures.)

When Chittering Host enters the battlefield, other creatures you control get +1/+0 and gain menace until end of turn.
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