Initially I didn't want any undo mechanics. My goal was for players to feel the pressure of the Xenospore's ruthless spread, and I was worried that an undo feature would take away from that experience.
However, a couple of key things changed my mind:
Player feedback:
Several playtesters found Xenospore quite challenging and felt that an undo option would help them work through the puzzles.
Game design:
Since Xenospore is a deterministic game, the Xenospore's reactions are 100% predictable once a player understands the rules. This means players can't abuse the undo feature to get new information. It simply lets them use trial and error to better understand the consequences of their moves.
Horror Vibe vs Accessibility:
Ultimately, I decided that while the horror vibe is important, accessibility and ease of use are more crucial for a better experience for a wider range of players. The undo mechanic helps with this without compromising the game's core loop.
Feel free to share your thoughts!