SenixPrime, Eco-Fighter

For every Prime spell you control, add a +1/+1 counter to this spell.

{1}{w}{r}{t}: Discard 1 card, search your library for a Prime spell, and put it at the top of your library.

When this spell has 3 or more +1/+1 counters on it, transform this creature. It retains its type as a creature in addition to its other types. (Loyalty abilities can still be activated.)