Legendary Creature - Rogue Otter Drake Hatcher Vigilance, prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.) Whenever this creature deals combat damage to a player, put that many incubation counters on it
Rampage 3
To determine the total cost of a spell, start with the mana cost or alternative cost you're paying (such as a spectacle cost), add any cost increases, then apply any cost reductions
Noits all three put together
Surveil / Mill Grim Flayer, Satyr Wayfinder, Elvish Reclaimer
And while protection from white is circumstantial, most Commander games will have at least one player with white mana in their deck, so that protection is rarely totally dead