I'd ignore their advice. One of the bad parts about Dragon Mountain is it is supposed to show how Kobolds can be deadly in D&D to high level characters but then goes and changes the rules (basically cheats) to make it happen.
Somedays I wonder if I missed anything by skipping 2e entirely.
This isn't one of them.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.