Anything that makes X tokens is going to be good, but lets go over some big-time spells that will make the table sit up and be super jealous
For example, Overkill's mana value is 3, because it costs two generic mana and one black mana
If Kroxa stays on the battlefield, each time he attacks the opponent will be forced to discard yet again
Breeder eliminates the need to include two to four useless Wartortles (or many other equally useless middle-stage evolutions) in your deck
Because at least MTGO automatically tells you all the activated abilities that are active and under your Agathas Soul Cauldron
It's a bit of a nonbo with Thalia, Guardian of Thraben itself, but even at three mana, the ability to add three, five, or even seven power to the board for just two mana is a pretty good deal for our aggressive decks