hyper mat card sleeves KMC Barrier PRO – Standard Size (100 Count) Each pack contains 60 sleeves that are both durable and thin Hyper Mat 80ct - White

The artwork also gives us a few clues

[11] In Japan, the packs feature art drawn by Mitsuhiro Arita, [12] while the English release has three possible packs, each depicting either Venusaur, Charizard, or Blastoise

Beastbreaker of Bala Ged Brimstone Mage Caravan Escort Champion's Drake Coralhelm Commander Echo Mage Enclave Cryptologist Guul Draz Assassin Hada Spy Patrol Halimar Wavewatch Hedron-Field Purists Hexdrinker Ikiral Outrider Joraga Treespeaker Kabira Vindicator Kargan Dragonlord Kazandu Tuskcaller Knight of Cliffhaven Lighthouse Chronologist Lord of Shatterskull Pass Nirkana Cutthroat Null Champion Skywatcher Adept Student of Warfare Transcendent Master Venerated Teacher Zulaport Enforcer

S-Tier Pikachu Ex Pikachu, is one of the strongest characters you can find in Pokmon TCG Pocket

The purpose of the Extra Deck is to contain Monster cards that do not belong in the Main Deck