You may pay {W}{U}{B}{R}{G} rather than pay the mana cost for spells that you cast.
"Willem put it on and started shooting sparks from his hands like some kind of wizard! Was supposed to be my turn next, but the blasted thing won't come off his hand. Send help."
—Brazen Coalition expedition dispatch
![Fist of Suns (Borderless) [The Lost Caverns of Ixalan Commander]](http://www.cardmerchanttakapuna.co.nz/cdn/shop/files/7d144602-605c-5d1a-93f0-25bcc51e64a0.png?v=1755864624&width=1445)