How about some more heroes? With more heroes you can get a lot of variety out of your games. You can also play them in solo (either as or against them) and even play 3-4P team games.

Battlecrest: Andmar Hero Set
Battlecrest: Kivani Hero Set
Battlecrest: Rin Mana Hero Set

Battlecrest is a card-based tactical skirmish game for 2 players (1-4 with expansions). With perfect information, players must truly outwit their opponent to win.

Characters are composed of 6-card sets featuring a hero card, a health tracker, and action cards. Occasionally a minion or item will replace an action card. The map is built of 6 cards as well, with the cards randomly placed in a set pattern.

Players take turns maneuvering their characters around the dynamic, and often dangerous map while unleashing powerful attacks. As action cards are used they open up new possibilities and empower the characters battlecrests. Build up to decisive strikes or refocus to get powers back. Every character has a unique set of actions and preferred tactics, so no two battles play the same.

description from the publisher