Okay so slow down a bit.

1: just how good is Haban at blade combat? Taja are not good. They’re the best. Ridahne would seriously struggle against one and she’s very good with a sword or a knife. His only decent chance of matching one would be using a gun or some other tactic (like the acid). And if he did engage with them he would not come out unscathed.
The reason I’m all particular about this is that there are not many of them and they’re a bit of a plot device, so they aren’t just expendable baddies.

2: I like the idea of him melting one’s face off though. To clarify, this is a beyond horrific thing to do in the eyes of the Azurei (the face tattoos are sacred and to even touch someone’s face without permission is extremely rude) and if Ridahne finds out he did it, it will be a big point of conflict later. Which could be fun. But I just want you to know what that action means in context.

But I also don’t wanna kill your vibe. Maybe there are two Taja and a group of eija (standard soldiers)? The Azurei fighting style is very much “hit and run”. They don’t have the tech or numbers to do brute force so they rely on strategy and stealth. Azurei is big on assassinations—-quick, quiet, doesn’t put too many of their own at risk more than there needs to be. They’d do an explosion, cause panic and throw their enemy off balance, kill either some key people or a handful, and disappear like ghosts. On the offensive, they are not typically a fight to the last man sort. Get in, do damage, get out.