Predalien Chestburster

As an additional cost to cast this creature, sacrifice a Yautja creature
This creature enters the battlefield with 3 time counters on it
{t}{b} Remove a time counter: This creature gains a +1/+1 counter
Offspring, Rapid Growth 2 (When this creature has no time counters on it, sacrifice it and search your library for a card named Predalien and play it without paying it's mana cost)