3 Uncommons There are 110 uncommons from the main set of Magic: The Gathering | Avatar: The Last Airbender that can be found in these slots
For one blue mana, Training Grounds reduces the cost of activated abilities of creatures you control by , with the limit being that it cant make activate abilities cost less than one mana
Frontline Rush Fury Fury of the Horde Garrison Excavator Gauntlet of Might Ghitu Encampment Giantbaiting Gift of Wrath Gimbal, Gremlin Prodigy Goblin Assault Goblin Offensive Goblin Rabblemaster Goblin Scouts Goblin Soothsayer Goblin Spymaster Goblin Surprise Goblin War Party Goblin Warrens Goro-Goro and Satoru Goro-Goro, Disciple of Ryusei Group Project Hazezon Tamar Hellion Eruption Heroes of the Revel Heroism Hexgold Hoverwings Horde of Boggarts Indentured Oaf Iroas, God of Victory Iron Man, Tony Stark Ivory Guardians Jaya, Fiery Negotiator Jodah's Avenger Jund Knights of Thorn
This is best known from an Alex Ross cover, although it is canon that Mary Jane (somehow) wore the Iron Spider armor for a few pages in 2015 (and also in some video games)
one in their Active Spot and up to five on their Bench
When unattached, sacrifices the previously equipped permanent, adding strategic depth
