So, aside from the decks and the Arena , There is the Discard pile, The Equipment screens and the Loading screen.

EQUIP Screen - Each Party member will have their Equipment. Most of the characters can equip 1 Weapon, 1 Accessory, 1 Armor and 1 Summon tool, Some Characters will not be able to equip all four at once just like some can equip more than four cards. You can equip only one card to any of your party members at each turn.

DISCARD/GLITCH Area - When an Party memebr is killed, all their items and the Character goes to the Discard pile. If The Charachter is Revived, He will come back to the Arena with all of the items he had. If there's no spaceo n the Arena, The Character will be sent to the Loading screen. You can recover items from there as well.

LOADING screen : There's your hand, composed by cards you obtain through the Deck. And there's the Loading screen, which works pretty much like a second hand, of course. Once a turn, you'll be able to draw a card from the top of your deck and then play a card from your hand. You can sacrifice the Deck Draw for a Loading screen Draw, Thing is that you will raw a random card from the Loading screen, and if you can't or Don't want to play it, it will go back to the Glitch area