Grimrock 2 will take place on the island of Nex; why an island? According to the developers, "the island is the perfect microcosm, where the party may explore dark woods, misty swamps, underground tunnels and ancient ruins without need to travel great distances. For us, an island is the perfect 'dungeon.'"
The inhabitants of Nex won't take kindly to your presence there, and Almost Human has completely re-written monster AI for the game. Monster behavior will depend on intelligence, so a smart enemy may call in reinforcements and use group tactics while a stupid brute may charge forward.
If it sounds like facing down monsters will be harder, the good news is that the game itself should be less of an obstacle, as the user interface has been reworked to be smoother and more convenient, requiring fewer clicks from the player. Potions, for example, no longer need to be crafted in the inventory - they can be mixed out-of-hand. Spellcasting is activated by holding down the mouse button while swiping across runes to create specific gestures.
Lastly, the developer revealed several new screenshots for the game, two of which show off the island's surface - it's quite a shift from the dark, dungeon corridors of the first game. Oh the times, they are a-changin'.