The D23 promo version of Maleficent, Monstrous Dragon, and every other promo from the event are likely to maintain their value over time, making them solid investments if you happen to have a few in your collection.
They grew fibrous mats of tentacles and chanted Emrakul's name in weird worship
I suspect that instead these are too expensive and small (for their size) to be much good
This is not your typical Simic deck, however: With Dragons abounding, it's not hard to close out a game, even if there are two or three board wipes along the way
Mutagen Man, Living Ooze Mutagen Man, Living Ooze gives a rare effect to reduce the cost of activated abilities
For half a decade? But on the other hand, why keep trying to reinvent some of these cards when you can just have them