Another option is to force your opponents to discard their entire decks , though milling a 99-card library is a daunting task and requires more set-up than card do damage or creature go smack

Common (36) 1 Brainstorm 1 Dark Ritual 1 Deny Reality 1 Commander's Sphere 1 Wayfarer's Bauble 1 Command Tower 1 Dismal Backwater 1 Evolving Wilds 1 Forgotten Cave 1 Path of Ancestry 1 Swiftwater Cliffs 1 Terramorphic Expanse 8 Mountain 8 Swamp 8 Island Uncommon (20) 1 Heralds of Tzeentch 1 Nurgle's Rot 1 Bloodcrusher of Khorne 1 Chaos Terminator Lord 1 Herald of Slaanesh 1 Noise Marine 1 Seeker of Slaanesh 1 The Lost and the Damned 1 Bile Blight 1 Bituminous Blast 1 Assault Suit 1 Sol Ring 1 Talisman of Creativity 1 Talisman of Dominance 1 Talisman of Indulgence 1 Worn Powerstone 1 Barren Moor 1 Crumbling Necropolis 1 Molten Slagheap 1 Temple of the False God Rare (41) 1 Lord of Change 1 Blight Grenade 1 Great Unclean One 1 Mandate of Abaddon 1 Mortarion, Daemon Primarch 1 Nurgle's Conscription 1 Plague Drone 1 Poxwalkers 1 Sloppity Bilepiper 1 Tallyman of Nurgle 1 Venomcrawler 1 Aspiring Champion 1 Bloodthirster 1 Dark Apostle 1 Keeper of Secrets 1 Khrn the Betrayer 1 Knight Rampager 1 Let the Galaxy Burn 1 Blood for the Blood God

This means there are 128 unique Mystical Archive cards , each with a variety of variants
Lets look at a few easy ways to make the right choice
By attacking together with the Characters played using "OP12-094 Monkey.D.Dragon", your opponent will have a tough time defending.
I also like the idea of using this as a combat trick in case someone comes your way, you can make a big powerful instant and then kill the attacking creature that came your way