Fun concept, but lacking in execution
It's basically solitaire with a twist. The core concept of the game is amusing. Match cards in ascending or descending order to charge your actions. The more you match in one turn, the more combo points you rack up, which boosts your actions. Simple. But, that's where the game falls short. It doesn't know whether it wants you to play your actions or go for combos. You charge actions (attack, spell, defend) by picking up cards of the same color (attack = yellow, spell = orange, defend = blue.) But once the action is charged (i.e. 3 yellow cards for basic attack,) additional cards of that color that you pick up go to waste. But, since that's how you build up your combo points, you're left with two choices:
1) Use the action as soon as it charges, which is weak and ends the turn, but at least you have more options next round, or
2) Build up your combo points for a boost, but then be left with meager pickings next round.
It's a lose-lose situation.
Another big issue is that practically everything ends the turn. Play an action, ends the turn. Use an item, ends the turn. Run out of cards to pick up, ends the turn. Reset the board, ends the turn. The core gameplay is picking up cards, but once you do, you don't have much to do other than end the turn.
And honestly, all of this wouldn't be all that bad if it weren't for the fact that the game solely relies on full RNG. While a handful of cards are faced up, the rest are faced down in stacks and you have no idea what the next card will be. You can't strategize and plan out your next turns, only pray to RNG-esus for one playable card.
I have had battles that took me 7 turns to win, but on a retry, only took me 2 turns. All based on pure luck.
This isn't a good mechanic for a tactical card game. There are easy ways to fix it and improve gameplay. I'm honestly surprised it was released this way, but I guess that's also why is giving it away for free.