Exactly. For the sake of those not in the know, D&D is just like a made-up-on-the-spot magic system, but unnecessarily complicated.
Wha?...
No explanation is EVER needed on how magic works, unless you specifically want to Do In The Wizard. It's magic. That just works for anyone who is willing to read a fantasy comic. If it doesn't, DnD doesn't exactly provide an explanation either.
Actually, DnD terms only complicate the explanation, if you keep in mind those who are not familiar with the system. I only knew what "rebuke" was because it was clearly what Reddy just did to Tsukiko's wights. It may be because of me not being a native speaker, but there is a lot of unnecessary for the story complication anyway. For example, V's barred school preventing vir from casting Teleport, which would translate into original magic system as "I can't learn that spell" and would be much simpler for a new reader. Malack's raising Durkon immediately with his staff, which would not require explanation AT ALL without a need to conform to an existing system.
No, they don't. They can't. They have no right to. Rich is aiming his comic at larger audience than just DnD fans, so he can't count on his readers knowing the rules. Tsukiko's new spell can hit Haley easily while having a harder time hitting Belkar's cat because it's different from the spell she used before, and that's all we need to know for that scene to make sense. "Attack roll" is an inside joke and an additional explanation for DnD geeks, and only complicates things for those who don't know.
Of course, if your audience is exclusively DnD geeks, then you can get away with less explanation... but that's pretty narrow.
What DnD gives you in a story sense is the settings, concepts - like paladins with their falls, clerics of Chaotic gods that must be themselves Chaotic, alignment system, races/monsters with their complex relationship and so on. It may give you inspiration for your own story alright, I know it firsthand (I'm in the middle of such story myself), and of course you would conform to the rules to not destroy your own point (provided you want to make some point). But having to follow pre-existing rules is a drawback of writing a "DnD story", not an advantage.
Well, rules also provide a source for rules jokes, which was, as far as I know, exactly the reason why OotS is a DnD comic. But you can't base a story on jokes. You can base a comic on jokes, and it doesn't make a comic any worse, but if you do want a story, you need a little more.