You get two 'Act of Treason' effects out of the flip, which is really good but only if your opponent has any creatures for you to take over
When you activate its ability and exile this legendary artifact, you can put an enlightened counter on any angel so your opponents cant win and you cant lose

Synthoids Abandoned Sarcophagus Abzan Banner Abzan Monument Academy Manufactor Accessories to Murder Accomplished Automaton Accorder's Shield Ace's Baseball Bat Acidic Dagger Acorn Catapult Acquisition Octopus Adaptive Automaton Adaptive Gemguard Adaptive Omnitool Adaptive Training Post Adarkar Sentinel Adrestia Adventurer's Airship Adventuring Gear Aegis Automaton Aegis of the Legion Aegis of the Meek Aeolipile Aeon Engine Aerial Doombot Aerial Surveyor Aerial Toastmaster Aeronaut's Wings Aesthir Glider Aether Refinery Aether Spellbomb Aether Syphon Aether Vial Aetherflux Conduit Aetherflux Reservoir Aetheric Amplifier Aetherjacket Aethersphere Harvester Aetherwing, Golden-Scale Flagship Aetherworks Marvel Aettir and Priwen Agatha's Soul Cauldron Agent of Acquisitions Agent's Toolkit Agility Bobblehead Air Response Unit Akroan Horse Akroma's Memorial Al-abara's Carpet Alacrian Armory Aladdin's Lamp Aladdin's Ring Alchemax Slayer-Bots Alchemist's Vial Alchor's Tomb Alhammarret's Archive Alibou, Ancient Witness Alibou, Ancient Witness Aligned Hedron Network All-Fates Scroll Alloy Golem Alloy Myr Alpha Myr Altar Golem Altar of Bhaal Altar of Dementia Altar of Shadows Altar of the Brood Altar of the Goyf

Again, some the confusion comes from those chapter abilities taking effect at a specific time, and occasionally containing triggered abilities
This tag team card combines not only the overwhelming power of Mewtwo and Mew, but also their value
Jeez, I'm treating you all today