It's not quite reactivity, but I think I'll talk about the Elementals in the game.
Right now - according to the pre-alpha videos - the Elementals can gain experience and level up. I don't think that's a good idea, because they're fragile, disposable, and only gain XP for things killed in the moments while they're up. You also may not want to use them in every single fight for mana-conservation reasons. That will lead to Elementals who will be quite under-levelled compared to the party. If they can't hit the enemy because of a level difference, that's also a problem.
I also don't think you should increase their level by putting your own skill points into "Summon X Elemental", like in Beyond Divinity. That's taking a skill point that could be much more useful for a PC and giving it to the fragile elemental, basically crippling one party member's abilities to get a summon of questionable usefulness and limited duration.
I think Elementals should automatically level up alongside the player, as they did in Divinity 2. That will let them be able to take and deal out hits without being one-shot killed or whiffing with every swing.
If you do it that way, then what good is the "Summon X Elemental" skill? I've got an idea for that as well. I am assuming skills will max out at 5 points.
Rank 1 will just let you summon an elemental.
Rank 2 will increase the base HP/MP of the elemental by some percentage, and giving it one selected skill from its element to use on its turn.
Each subsequent point up until the max of 5 will further increase its HP/MP and grant it additional skills.
A maxed out Elemental will have quite a bit more HP and MP (say, 50% more), and it will have up to 4 skills it can use. Let's say that it can only learn skills that the summoner has learned, but for balance reasons, we can have its skills be less powerful than the summoner's skills.
Thoughts?
