No, las fichas que pone son copias de Pack Rat, o sea que tienen coste de maná 1B (necesitarías tener 2 contadores en la Ratchet Bomb para matar las Pack Rat).

Pack Rat
1B
Creature -- Rat
*/*
Pack Rat's power and toughness are each equal to the number of Rats you control.
{2}{B}, Discard a card: Put a token onto the battlefield that's a copy of Pack Rat.


Ratchet Bomb
2
Artifact
{T}: Put a charge counter on Ratchet Bomb.
{T}, Sacrifice Ratchet Bomb: Destroy each nonland permanent with converted mana cost equal to the number of charge counters on Ratchet Bomb.