There's nothing wrong with leaving Matzalantli, the Great Door closed and never transforming it
Tigger can quest for one, but he can gain an additional questing point if you play an action, making him work best in decks with a fair amount of singing
Alternatively we could also see it as the three time layers, past, present and future, as Teferi comes into this timeline from the future into this present to learn about the past and the Sylex
I was indexing my Magic: The Gathering inventory recently and I found a card from M19 that's identifier is 287/280
The color wouldn't be able to deal with anything permanently, but would instead just keep putting off its problems on the theory that it would win before it has to deal with them
So, if you have four Vampires, they'll be boosted by +3/+3 (as they do not count themselves in the stat boost)