What cards are similar to On an Adventure Card
It works well in control buying time until mass removal and it works well in aggressive decks proactively taking out any creature they like in a very cost effective way
Then theres New Blood, a very specific card that lets you take control of a creature an opponent controls, but is one of the few ways to permanently steal creatures without access to red or blue mana
Alrund's Epiphany Alrund, God of the Cosmos Battle Mammoth Burning-Rune Demon Eradicator Valkyrie Esika, God of the Tree Goldspan Dragon Hakka, Whispering Raven Halvar, God of Battle Haunting Voyage Kaya the Inexorable Koma, Cosmos Serpent Niko Aris Orvar, the All-Form Quakebringer Resplendent Marshal Starnheim Unleashed Sword of the Realms The Prismatic Bridge Tibalt, Cosmic Impostor Toralf's Hammer Toralf, God of Fury Tyvar Kell Valki, God of Lies Vorinclex, Monstrous Raider
Unfortunately, the 3-star immersive cards are the rarest pull outside the Crown Rare cards, so this may take some time to complete, but given how many packs it may take to meet Mew's requirements, odds are you may have the others by the time you unlock that one
