If you already have good blink targets, like various Thassa, Deep-Dwelling decks in Standard, then Yorion, Sky Nomad is an incredibly powerful card to have access to in every game
Both cost two mana and are relatively innocuous creatures by themselves
Azlask, the Swelling Scourge Bosh, Iron Golem Brisela, Voice of Nightmares Clara Oswald Codie, Vociferous Codex ED-E, Lonesome Eyebot Emrakul, the Aeons Torn Emrakul, the Promised End Emrakul, the World Anew Error-9, Viral Node Faceless One Fizik, Etherium Mechanic Galactus, Devourer of Worlds Golos, Tireless Pilgrim Goro Rel, Scourge to Spiders Graaz, Unstoppable Juggernaut H.E.R.B.I.E., Lovable Robot Hanweir, the Writhing Township Herigast, Erupting Nullkite Hope of Ghirapur Iron Spider, Stark Upgrade Jocasta, Automaton Avenger Karn, Legacy Reforged Karn, Silver Golem Kozilek, Butcher of Truth Kozilek, the Broken Reality Kozilek, the Great Distortion Krang, Utrom Warlord Liberator, Urza's Battlethopter Living Brain, Mechanical Marvel Machine Man, Model X-51 Marvin, Murderous Mimic Memnarch Molecule Man Morophon, the Boundless Omarthis, Ghostfire Initiate Page, Loose Leaf Ramos, Dragon Engine Silver Surfer, Galactus's Herald Spider-Slayer, Hatred Honed Super-Adaptoid Syr Ginger, the Meal Ender The Capitoline Triad The Dawning Archaic The Peregrine Dynamo The Prismatic Piper The Vision The Walls of Ba Sing Se The Warring Triad Traxos, Scourge of Kroog Traxos, Scourge of Kroog Tri-Sentinel, Act of Vengeance Ulalek, Fused Atrocity Ulamog, the Ceaseless Hunger Ulamog, the Defiler Ulamog, the Infinite Gyre Ultima, Origin of Oblivion Ultron, Artificial Malevolence Ultron, Machine Overlord Urtet, Remnant of Memnarch Victor Mancha, Runaway Vision, Synthezoid Avenger Viv Vision, Teen Synthezoid Zabaz, the Glimmerwasp Zhulodok, Void Gorger
Teysa works better with some cards than others and being a touch on the luxury / win-more side of things you do have to be a little careful with her
