Make poison damage possibly variable (might as well since effects is a count). Scripts might find it handy.
Add check for gear kind of hedgehog on invulnerability effect. This probably fixes bug #766, is similar to change in previous
r2a1483d91977 and was introduced by
r7d925e82e572
well. let's fix this at least - only apply to gears that are actually hedgehogs, not just ones associated with a hedgehog (which can be pretty much any gear since damage tracking was added)