Hello everyone!

Do I get to fight Arklem eventually? Right now he's in Maugrim's prison and he suggested that we team up. Thing is, I'm a ranger, and rangers are good guys. If I were lawful good I wouldn't mind letting him go since he didn't commit any crimes that I know about.

No you don't. Aside from the fact he is a lich -- is that a crime in and of itself? -- who gained that state by allying with a baatezu against the Silver Marches, he's also killed noblemen, imprisoned Drizzt in the abyss, and killed thousands by detonating his staff inside the Hosttower. No crimes? I don't think so. It's a shame you're not given the chance to end his sorry existence then and there: you need him to open that door.