Whew that's a lot!
OK, DC 20 is fine.
I think I must have missed the word "homebrew" there somewhere!
I do like the 3d6+10 days for each +2 boost.
I like the aggressiveness bit, but the original talks about "fighting to the death." So shouldn't the host attack until the offending creature is dead or flees, not just for a while after the provocation ends?
I was attempting to use the wording of some WotC Rage and Frenzy special abilities, but have no objection to including a "fighting to the death" phrase.
Also, I was going to mention the
calm emotions spell in there but somehow forgot.
How about changing that sentence to:
If the creature fails this Wisdom check they will attack the provoking object or creature in a violent frenzy. This frenzy lasts until the host dies, loses consciousness, or the provoking creature or object is either out of their sight for [
1d6? or 1d4? or 1d8?] rounds or destroyed; if the provoking creature flees the host will pursue them. A
calm emotion spell will stop the frenzy if the host fails their Will save.
The simplified heart attack paragraph is good. Let's stick to that. The red values are ok. Maybe the heart attack kills over 3d10 rounds? That averages about a minute, so it's a major heart attack I guess, which sounds right.
3d10 is 16.5 so that's 99 seconds, or 1.65 minutes. If you want a minute, how about 4d4 rounds? That averages to exactly 60 seconds!
Also, there's some mixes of DC10 and DC5 in there that need cleaning up. I think I'll start it at DC 5, so an exceptionally hale Con 18 character can reliably fight for at least one period before risking the fatal heart attack.
Revision:
Once all a powerslug host's physical ability scores gain a +8 alchemical bonus, the enormous strain on their body damages their heart. If the host performs extremely vigorous activity, such as combat, for 1d4+1 rounds, they must succeed at a DC 5 Constitution check or suffer a fatal heart attack and die over 4d4 rounds. The save must be repeated each 1d4+1 additional rounds of vigorous activity, with the DC increasing by +1 for each previous check. The rounds of vigorous activity need not be consecutive or on the same action. The accumulated strain of vigorous activity can be healed by rest down to the minimum of DC 5: a night's sleep lowers the Con check DC by –1, a full day's rest lowers the DC by 1d2, and long-term care with a DC 15 Heal check lowers it by –3 per day. A
restoration or
cure critical wounds spell can prevent a host dying from a heart attack, the
restoration also lowers the Con check DC by –5 (minimum DC 5). A
heal or
greater restoration completely cures a fatal heart attack and sets the Con check starting value to DC 5.