During this game's development, I was one of the 4 designers who assisted in the creation of the core gameplay systems. Features initially documented in Excel before being implemented into the game and further iterated from there.
Early into development, features were expirimented with within TableTop Simulator to simulate gameplay while the engine was in development.
Once the engine was fully operational, we were able to organize each of the mechanics based on both how long it would take to implement and or how popular of an idea it would be for the team within Excel. Later into development, we ended up using this to also track the current progress on these mechanics to keep the team coordinated. Units, Enchantments, and Spells were all balanced around when something didn't feel to early to play to maintain the challenge curve of the combat.
After the mechanics were created by the programmers, I was then able to iterate on the exact values behind the cards through continuous testing. Our team also playtested this game every few weeks throughout development to ensure the mechanics were easy to understand and balanced. These values were also used for encounter design in order to enforce the challenge curve of the game during a run.

The other largest system the game has excluding the combat itself is the reward system. While early iterations utilized a draft style system, the game ended up utilizing the more classic "choose your reward" system. Early iterations of this allowed the player after beating a stage to choose what type of reward they wanted. However, this concept was reworked to split them into two different rewards to balance the challenge curve of the game.

Both the default and the Chest reward variants let the player pick cards to add to their deck. To allow more freedom of choice, the player is guarenteed to have at least 1 basic unit, 1 spell, and 1 enchanted unit.

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