Laboratory Vermin

Rally — Whenever Laboratory Vermin or
another Ally enters the battlefield under your control, you may have Rat creatures you control
gain infect until end of turn. (This creature deals
damage to creatures in the form of -1/-1 counters and
to players in the form of poison counters.)
Laboratory Vermin's power is equal to the
number of Rats you control plus 1, and it's
toughness is equal to the number of Rats you
control.