From the website:
Are you a long-time Fizzhead who got your special edition models before Relic Knights had a game? Then the special edition card pack is for you!
This pack includes tracker and reference cards to field your special edition models in your games of Relic Knights: Darkspace Calamity.
-Suicide Queen — Unique
-Ayu Beat — Unique
-Candy Heart — Unique
-Kisa — Questing Knight
-Scratch — Cypher
Please Note: You do NOT need to buy these cards if you are purchasing the current special edition models, cards are included.