The Crown Prince

Whenever you cast a single-colored
non-permanent spell, exile it with a fuse counter.
Whenever two cards of different colors are exiled
with fuse counters, remove a counter from two of
them and fuse the elements.
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Green, Red - Deal 4 damage to each opponent.
Red, Blue - Gain control of target creature
opponent controls until end of turn.
Blue, Green - Target player gets 2 poison
counters.