Life Tap

Curses a group of monsters so that damaging them gives the attacker life.

Life Tap is a level 18 Necromancer curse (Curses tree, requires Iron Maiden; it unlocks Lower Resist with Decrepify). Anyone who lands a physical hit on a cursed monster, in melee or with a missile, heals 50% of the physical damage that landed. The 50% is the same at every level; levels buy duration, 16 seconds at level 1 to 61.6 at level 20, and radius, 2.67 yards to 15.33. Mana is a flat 9.

The numbers

• Heal is calc1 ln56: Param5 50 with Param6 0 a level ("Damage % returned as healing to attacker baseline" and "per level" in skills.txt). It never changes, so the tooltip's "Heals: 50% of attack damage" line is left out of the table.
• Duration is Param3 400 frames plus Param4 60 a level, at 25 frames a second: 16 seconds at level 1, +2.4 a level, 61.6 at level 20, 85.6 at level 30.
• Radius is Param1 4 plus Param2 1 a level, ×2 ÷ 3 for yards: 2.67 yards at level 1, 15.33 at level 20.

The duration and the radius read the full skill level, so +skills count.

How it works

Life Tap is a cast curse: no attack roll, no damage of its own. It puts the lifetap state on every monster in the radius around the targeted point. The state's events are damagedinmelee and damagedbymissile, so both melee attacks and missiles trigger the heal; spell damage does not. The Basin's rules for the heal:

• It is 50% of the final physical attack damage. The target's physical resistance reduces the damage and so the heal: cursing and hitting an immune to physical monster returns no life.
• It is not Life Leech. Unlike "% life stolen per hit", the unit damage modifier, the weapon-damage fractions of Multiple Shot, Strafe, Blade Fury and Blade Shield, the Nightmare and Hell leech penalties and the target's drain effectiveness do not apply to it. Life Tap heals the full 50% in Hell against a monster whose drain effectiveness would cut leech to nothing.

The heal goes to whoever lands the hit, so a mercenary or a summon hitting a cursed monster heals itself; the Necromancer only heals from his own physical hits.

The curse takes the monster's single curse slot, so Amplify Damage or Decrepify cast afterwards replaces it.

Synergies and +skills

No synergies: Life Tap has no synergy lines in skilldesc.txt and feeds none. The two lines that grow read lvl, so a +1 from items is worth one hard point: +2.4 seconds and +0.67 yards. The 50% does not move for either.

Against players

A player's hit on another player is cut to 17% of its value (difficultylevels.txt PlayerDamagePercentVSPlayer) before anything else, and the heal is 50% of what lands after that. The Basin's page records no other player-versus-player rule for this curse. See Player versus Player.

Build notes

• One hard point gives the whole 50%; everything after is 2.4 seconds and 0.67 yards a level. Level 20 is 61.6 seconds over 15.33 yards for 9 mana.
• It is the heal that works where Leech does not: no Hell penalty, no drain effectiveness, no weapon-fraction rule. Physical immunes are its one blind spot.
• A melee mercenary or a melee summon under it heals itself with every hit; that is its common use for a caster.