After they made a pretty weak mythic X-damage spell (Comet Storm), it appears they are trying everything they can to make the next mythic X-damage spell actually worth the red price tag
Like most Magic: The Gathering cards, the value of Corroding Dragonstorm depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (Tarkir: Dragonstorm)
Guarantees landfall every turn that's just the bee's knees
Whats interesting here is the title of the card is where the cards types and subtypes are typically placed, with this text now brought down to the cards ability text box
Any dice-rolling card with some promise and some scarcity is moving up thanks to this new Commander and the dream of pulling off Luck Bobblehead
Its a solid modal creature that cares aboutyou guessed itattacking, though it immediately impacts the board since Ceasar doesnt have to be the attacking creature to trigger the ability