Love the atmosphere. Love the plot/story and the mystery involved. Love the non-player characters and enemies (ranging from otherworldly beasts to robots to ghosts to possessed people). Love how extremely different each world/area is. It's neither linear, nor too 'open world'. And every game is a bit different because of the way worlds/areas are partly randomly generated and presented in a different order for each player.
Gameplay is a tonne of fun. There's challenge, but it's not over the top difficult. Enemies, whether standard, elite, or boss, vary dramatically and can therefore require quite different strategies. And there are so many secret areas to discover and puzzles to solve that it's always an adventure.
The character choices and progression, and the weapon and mod and ability progression systems are interesting and varied. At first, it felt like it was going to turn out to be one of those really grindy games with slow progression and probably in-app purchases to speed things up. But it has definitely not turned out this way. Rather, it's gradual enough to add to the challenge and encourage extra exploration, without ever getting boring or dragging on too slowly. Just the right balance.
Controls are refined. Movement and targeting is extremely smooth and natural, and camera angles are just right. Up there with the very best in quality.
Most of all, the more I play Remnant II, the more I feel like it's a game designed by people who genuinely play games themselves and really care about what they're doing. Such a refreshing surprise!!!