You have money on the comission of artwork, the sets are smaller, easier to fill, and the cards get the better looking art
Two mana to deal 3 damage to a creature
Umbral Collar Zealot What makes the Vivi Soul Cauldron deck so strong is it is a combo deck, but one that is also full of creatures that cannot be ignored on their own
It has also saddened me in the past that a Mystic SnakeMystic Snake wont do anything useful with sorcery speed blink or copy effects, and while this is a very minor complaint I am also pleased that Fangkeepers FamiliarFangkeepers Familiar will have things to do in those situations
But the CMC on Varragoth is so low that I really dont think it should be a problem if you have to recast it
Swiftfoot Boots can protect Purphoros or all-stars like Krenko, and Ashnod's Altar is a fine way to sacrifice tokens for extra mana for those costly curve-toppers