Did finish the game on Hard during 1st playthrough, I didn't play blind as I use cheat to see what's ahead and plan accordingly (tried my best not to cheat items/HP as best as I could).
And I believe I got every unit available? Not sure tho lol
I wish someone made cheat table like previous game, Frontier & Hollow, where you can even edit unit skills.
Just in case tho. Sometime I want the game to be harder. That being said, not fond of this game after playing Hollow sadly, new player should start with Frontier, GAIA, and Hollow. The UI and aspect ratio really ticked me off.
(not to mention it's tower defense, far different than the previous 2 international)
I know there's cheat for GAIA but it requires Mod Engine. Sorry, but no. I'm still trying to make my own cheat table but keep failing, yes it's been years. And yes I've completed the game multiple times.