Onyx Pit's Iceweaver

Whenever Onyx Pit's Iceweaver deals combat
damage to a creature, put an ice counter on that creature at the end of combat. (Permanents with
ice counters on them are snow.)
Whenever Onyx Pit's Iceweaver deals combat
damage to a player, add {s} of any color for each
snow creature they control. (Snow mana can only
be spent to cast a snow spell or to activate a snow permanent's ability.)