Regeneration (GnollHack)

Regeneration effects, for both hit points and energy, directly modify the bearer's natural hp/mana recovery in GnollHack. (Energy/Pow is called Mana in GnollHack, by the way.) Likewise, natural hit point and mana recovery is very different from how it is in vanilla NetHack, scaling only off the maximum values for both.

Hit Point Regeneration Rate

The time it takes for a player or monster in the game to return to full health is determined by a TURNS_TO_FULL variable.

If their max HP is greater-than-or-equal-to their TURNS_TO_FULL, they regain $(\frac{\text{Maximum Hit Points}}{\text{Turns to Full}})$ lost hit points each turn. This rounds down.

If their max HP is lower than their TURNS_TO_FULL, they regain 1 lost hit point every $(\frac{\text{Turns to Full}}{\text{Maximum Hit Points}})$ turns, plus-or-minus 1 turn. This rounds up.

All sources of hit point regeneration in GnollHack modify the "Turns to Full" variable. Unlike vanilla NetHack, GnollHack has five different tiers of enhanced regeneration, none of which modify nutrition burn (though the ring of regeneration now comes with extrinsic hunger). Only your highest-tier regeneration effect applies.

Regeneration Tier	Turns to Full	Approx Regen/Turn
0 ("Default")	320	Max HP/320
1 ("Regeneration")	$min[\text{Max HP},160]$	$max[(\text{Max HP}/160),1]$
2 ("Rapid Regeneration")	$min[(\text{Max HP}/2),80]$	$max[(\text{Max HP}/80),2]$
3 ("Rapider Regeneration")	$min[(\text{Max HP}/4),40]$	$max[(\text{Max HP}/40),4]$
4 ("Rapidest Regeneration")	$min[(\text{Max HP}/8),20]$	$max[(\text{Max HP}/20),8]$
5 ("Divine Regeneration")	$min[(\text{Max HP}/16),10]$	$max[(\text{Max HP}/10),16]$

Mummy Rot

Mummy rot is a sickness in GnollHack that damages your hit point regeneration. It's given by the claw attacks of mummies that happen to get through MC.

• When your regeneration tier is zero, it sets your TURNS_TO_FULL to minus-960. This means sufferers actually lose hit points over time, instead of regaining them, though at roughly one-third the rate that they would otherwise regain them.
• When your regeneration tier is above zero, it insteads switches your hit point regeneration to $[(\text{regeneration tier})-1]$ hit points per turn.

Mana Regeneration Rate

Mana regeneration uses the same equations as regular regeneration, but with TURNS_TO_FULL_MANA and Maximum Mana Points instead.

Mana Regeneration Tier	Turns to Full Mana	Approx Mana Regen/Turn
0 ("Default")	240	Max Mana/240
1 ("Energy Regeneration")	$min[(\text{Max Mana}*\frac{2}{3}),120]$	$max[(\text{Max Mana}/120),1.5]$
2 ("Rapid Energy Regeneration")	$min[(\text{Max Mana}/3),60]$	$max[(\text{Max Mana}/60),3]$
3 ("Rapider Energy Regeneration")	$min[(\text{Max Mana}/6),30]$	$max[(\text{Max Mana}/30),6]$
4 ("Rapidest Energy Regeneration")	$min[(\text{Max Mana}/12),15]$	$max[(\text{Max Mana}/15),12]$

As with hit point regeneration, there is no stacking in energy/mana regeneration; only your highest-tier energy regeneration effect applies.

New Sources of Regeneration

Regeneration

• red dragon scale mail
• healing mushroom (temporary)
• potion of lesser regeneration (for 1d10+40 rounds)
• potion of regeneration (for 1d10+40 rounds -- applies a higher tier)
• potion of greater regeneration (for 1d10+40 rounds -- applies a much higher tier)
• staff of life
• iuon stone of regeneration
• Ruby Rod of Asmodeus
• The Tooth of Tarrasque

Energy Regeneration

• white dragon scale mail
• mana mushroom (temporary)
• ring of replenishment
• Ruby Rod of Asmodeus
• The Serpent Ring of Set