Okay, so unless I'm mistaken, CCGs take a lot more investment to get going than the average card/board game. For that reason, this isn't one of my main projects rn so much as a little pet idea. For anyone familiar with Duelyst, this game would be kinda similar to that (except units would heal at the end of turns, like in Magic). You have a 9x5 grid board, with a general at each end. Kill your opponent's general to win. The key idea that this game is based around is what I call the "sacrifice" system. Instead of having designated mana/energy/land/whatever cards, every card would serve as 1 point of resource. The entire game revolves around this mechanic. To deploy a 1-cost unit, discard one card. To cast a 3-cost spell, discard three cards.
The combat would also make use of the sacrifice mechanic, where each unit would not only have base Attack and Health stats, but would also have Max Attack and Health stats. Whenever an attack is initiated, the attacking player can sacrifice cards to boost their unit's attack by one point per card, up to the unit's max attack. The defending unit can do the same with health. Both players reveal the number of cards used at the same time, so it creates a bit of strategic uncertainty without introducing any unnecessary randomness.
I'm debating whether or not it would be a good idea to allow players to sacrifice units that are already deployed, but idk (maybe it could be a special ability for a Hero unit)