[PvK]

Almost all 2d6 rolls in D2 are open-ended, so I'd expect so here too.

Two spell foci probably don't add (few misc items of any kind add).

I expect attacker needs to win to succeed, not just tie, but don't know.

Astral 6+ is a reasonable approach for pretenders, in my book.

I think you're more or less right AFAIK, for the limited case you're considering.

It'd be pretty lame/uber if Soul Slay always had a good chance to kill anything with a soul. Soul Slay is hugely powerful as it is, if not against very high MR targets.

PvK