Yorion Dimir Inverter
A Pioneer deck, by HappySandwich
5th place at a tournament in Magic Online on 2020-05-20

Maindeck:

Creatures
4 Inverter of Truth (Banned in Pioneer)
4 Thassa's Oracle

Enchantments
4 Omen of the Sea
3 Shark Typhoon
4 Trial of Ambition

Instants
4 Dig Through Time
4 Fatal Push
2 Hero's Downfall
2 Neutralize
4 Opt

Legendary Planeswalkers
4 Jace, Wielder of Mysteries
3 Narset, Parter of Veils

Sorceries
4 Thoughtseize

Basic Lands
8 Island
3 Swamp

Lands
4 Choked Estuary
4 Drowned Catacomb
4 Fabled Passage
4 Fetid Pools
2 Temple of Deceit
4 Watery Grave

Legendary Lands
1 Urborg, Tomb of Yawgmoth

Sideboard:
2 Damping Sphere
4 Mystical Dispute
2 Kalitas, Traitor of Ghet
1 Yorion, Sky Nomad
1 Ashiok, Nightmare Muse
2 Collective Brutality
3 Cry of the Carnarium