This is a tactical RPG created using RPGMaker MZ and a plugin that converts the standard turn-based RPGMaker battles into something more like Fire Emblem, but looking at the game summary it was originally started in Godot and then the RPGMaker entry was created right before the deadline after the original Godot project got corrupted. Given that context, it's a pretty solid salvage attempt and I'd love to see what can be done using the entire jam duration.
Understandably the game content and balance feel unfinished, but I appreciated that the sample mission had a clearly defined objective and a simple narrative about holding out against continuous enemy reinforcements until help arrives from friendly airstrikes. During my first playthrough I treated it as an ordinary 'exterminate everything' kind of mission and got frustrated, but the second time I played defensively and it worked out surprisingly well.
Issues with project file corruption can be prevented by using a source control system such as Git. Even if you're working on something solo, source control will at least provide backups and allow you to easily roll back any new changes that introduce too many bugs. I always use source control even on solo jams because I develop on both a laptop and a desktop and have to frequently switch between the two.