Naldrid, Soul of Abyssal Frost

Void Portal-{x}{u}{u}{b} You may cast an exiled
spell without paying its mana cost, then exile the
top X cards of your library
Frozen Void-Whenever a spell played from exile,
tap target nonland permanent and put a stun
counter on it
Abyssal Soul-Whenever a stun counter is
removed, add three mana in any combination of
colors to your mana pool