Untap all green and/or blue creatures you control during each other player's untap step
If you want to play Esper colors (blue, white, and black), then Dragons such as Chromium and Dromar, the Banisher are eligible
This is because, despite many faults in the implementation in Standard, the Universes Beyond Commander decks are typically themed to perfection and draw on the source material to identify strong mechanical comparisons within Magic that make the game easier to understand
The Foundations expansion is essentially designed to help you build a bigger Foundation with the Magic trading card game, as the name implies
And this is from an exhaustive list of Twin answers that see heavy play in the Modern format
Disciple of Freyalise / Garden of Freyalise Disciple of Freyalise looks like a Limited card that allows you to cash in a creature for cards, but considering that its an MDFC, the playability grows a lot