Regeneration rate

Version 0.30: This article may not be up to date for the latest stable release of Crawl.

Your regeneration rate is the speed at which your character recovers HP. It is affected by many things, almost all of which stack.

Rate Math

Your base regeneration rate (BRR) is calculated as follows:

20 + MHP / 6

So for every 1 max HP, BRR increases by 1/6.

Modifiers

Total regeneration rate (TRR) is modified as follows, in this order:

• The Regen+ property adds 80 per instance, which stacks.
  • An artefact may generate with Regen+.
  • An Amulet of regeneration gives a rank of Regen+.
  • A troll leather armour has Regen+.
    • The moon troll leather armour unrandart adds another rank of the property (Regen++ in total).
  • The regeneration mutation adds a rank of Regen+ per level.
  • The robe of Vines gives Regen++++.
• The demonspawn mutation Powered by Death has a chance to add a temporary regen bonus of up to 100*level. Further kills can increase this up to a maximum of 1000-1200, but falls by 100 every 2-5 turns.
• If you are a vampire and Alive, add 20.
• If you are sick or have -Regen, set your rate to 0 if there are monsters in your LOS.
• Jiyva adds anywhere between 80 and 160, depending on piety level.
• Trog's Hand adds 100.

Because the last two effects are applied last, they are not modified by any other factors, and can heal you even if you have -Regen.

Every turn (10 auts) you accumulate regeneration points equal to your TRR. When you accumulate 100 points, you heal 1 HP, and excess regeneration points are carried over to the next turn.

If your last action didn't last 10 auts, the amount of regeneration points you gain is scaled with the amount of time taken; your regeneration rate will remain consistent regardless of how quickly or slowly you are acting.

At 100 MHP, your BRR is 36.6. In order to get 50 BRR (regain 1 HP every 2 turns), you would need 180 MHP; for 100 BRR (heal every turn), you would need 480 MHP. Items or mutations that increase regeneration are far more efficient at raising your regeneration rate than stacking HP.

Examples

• You have 30 MHP. Your BRR is 20 + 30/6 => 25. It will take 4 turns to accumulate 100 regeneration points and heal by 1 HP. Your healing rate is 1 HP for every 4 turns.

• You have 180 MHP. Your BRR is 20 + 180/6 => 50. It will take 2 turns to accumulate 100 regeneration points and heal by 1 HP. Your healing rate is 1 HP for every 2 turns.

• Same as above, except you're wearing a troll leather armour, which adds 80 to this rate. Your TRR is 50+80 => 130. You accumulate 100 regeneration points and heal by 1 HP every turn, with 30 left over. Your healing rate is 1 HP every turn, with an additional HP every 3.33 turns.

History

• Prior to 0.30, base regeneration rate was MHP / 3 if under 60 max HP, and MHP / 6 + 10 if over it. Regeneration rate was lower at all max HP levels.
• Prior to 0.28, the Regen+ property gave a bonus regen of 100 (1.0 HP/turn) instead of 80.
• Prior to 0.27, the Regen+ property gave a bonus regeneration rate of 40 (0.4 HP/turn) instead of 100.