Thanks! Super glad you liked the terrain, that was quite fun to program.
Yep, the time travel mechanics have a high learning curve. I just barely didn't have enough time to add the intro level, which I think would have helped. It's tricky to get used to, but the best strategy by far is to have your first self use Defend and soak some hits (usually 4 or 5 turns is sufficient) and then have 2 or 3 more selves come and attack the enemy while the enemy is attacking the defending self.
Keep an eye out, I'm hoping to polish this and release it on android/ios later this year!