Having the ability to ramp into high heaven in Green, allows all the pricey enchantment and artifacts to be affordable for Bello
I would cut Alesha's Legacy, Overwhelming Remorse, and Putrefy in favor of Merciless Executioner, Insidious Fungus, Grist, the Hunger Tide, Foundation Breaker, and Acidic Slime
While you may think that destroying the target of the mutating creature would cause the spell to fizzle, the mutate spell on the stack just goes onto the battlefield as a normal creature instead
There's a range of impressive abilities that Verrak can double, most notably allowing Fetch Lands to put two lands into play, serving as stellar and efficient mana ramp
19 Hex Maniac A fairly useful Supporter Card, Hex Maniac has a pretty annoying ability that can really mess up some players out the gate