Ren has the ability to shapeshift into a fancy knight, so he's got a sword and every intention of going for the monster's weak points as soon as he spots them, since he's pretty good at picking out that sort of thing.

His sword also has some long range attack ability - they're single hit magic, basically, but one of them is a lightning strike, which might help with the whole "keep it out of the shadows" aspect. He's also here to snap people out of things as best he can, since he is relatively resilient to psychological manipulation techniques considering...he used to do that sort of thing to people himself. Whoops.