For
turn based: Divinity Original Sin 2 easy. No game allows for even close to as much creativity or complexity the system here has built in. It, far, *far* more than any other turn based game I've played, requires players to think about natural cause and effect and push those systems to the limit, and what a far limit that is. That Larian made this off the back of just setting stuff into place and seeing where the chips fall makes it even more impressive.
Action RPG: Valkyrie Profile 2. I'm surprised no one else said this [that I saw]. Feels like a fighting game in a lot of ways, and the "stop/move" mechanic, combined with the dodge, the occasional arena mixup, and the "target enemy leader" stuff all work together perfectly, and it doesn't feel like I'm playing a watered down version of a non-RPG action game.
Melee Action Game: Honestly, DMC3 (with style switch). While DMC5 has more characters, with weapons which have more moves on them, the weapons and styles in 3 all feel more unique (nothing like Nevan at all, for instance) and like they have more depth to each individual move or tier (ie, something like Trickster lvl 3)...albeit with fewer constituent parts. As I was playing through 5 I was constantly wishing I could do some moves from 3 - like where's my Free Ride? No wallrunning? Shame.
Shooting Action Game: Controversial pick, but BF4. Now, no, the specific weapon handling is worse than something like any of the CoDs, it's less fluid than either of the Titanfalls, and it lacks the momentum loops of either Doom 2016 or any of the Halos. Yet, as a system, which is to say, a combat group of all the constituent parts to be used on enemies, this is untouchable thanks to the vehicles and customization. It's organic to an incredible degree, enough to have its own brand of Moments, and invokes a sense of being on a true combined arms warzone unlike anything else.
Honorable mention: Bujingai.
Wow, and I thought I was the only one who ever played Bujingai.