Rakdos Elemental

When Rakdos Elemental enters the battlefield,
target opponent discards a card if {b} was spent
to cast Rakdos Elemental.
When Rakdos Elemental enters the battlefield, it
deals 2 damage to target player or planeswalker
if {r} was spent to cast Rakdos Elemental.
Evoke {b/r} (You may cast this spell for its evoke cost.
If you do, it's sacrificed when it enters the battlefield.)