Meruem

Trample
Up to X mana doesn't empty from your mana
pool as steps and phases end, where X is the
number of +1/+1 counters on Meruem. You
may spend mana as any color to cast insect
spells or activate insect abilities.
Sacrifice a creature, {t}: Meruem gets a +1/+1
counter and gets all activated, static, and
triggered abilities of that creature.