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From the Codex of Ultimate Wisdom

Reptile Slayer

A folio of the realm

Reptile Slayer

The Reptile Slayer is a Super Slayer item-property tag that grants a 2× damage multiplier against the broad reptile creature category — every dragon, drake, lizardman, snake, ophidian, and serpent in Britannia. As a Super Slayer, Reptile Slayer covers a wider range of monsters than any individual lesser-slayer (which targets a single creature type), making it one of the most popular all-purpose end-game slayer choices for melee, archery, and throwing builds. Its opposing slayer is Arachnid Slayer — a weapon tagged with one cannot be tagged with the other.

Reptile Slayer applies as a multiplier after the Damage Increase cap and after the Base Damage bonus stack — it is layered on top of the standard 300% damage cap, separate from it. Against a matching reptile target, a Reptile Slayer weapon's swing is doubled at the very end of the damage calculation, before Resistances.

Damage formula with Reptile Slayer

Damage = Base_Damage_Roll × (1 + AllMultipliers / 100)        ← within 300% cap
       × ReptileSlayer_2x                                     ← if target is reptile
       × Exceptional_1.30_to_1.35                             ← if Exceptional tagged
       × apply_Phys_split_resists(target)

Concretely, a Sampire on an Exceptional-marked Reptile Slayer Halberd against a Greater Dragon gets:

Term Multiplier
Base Damage Halberd Roll(18, 26) — average 22
Tactics + Anatomy + STR + Lumberjack + DI stack up to +296.25% (capped at +300%)
Reptile Slayer (matching) × 2.0
Exceptional × 1.35
Phys split (default 100%) × (1 − target.PhysResist / 100)

The 2× from Reptile Slayer doubles every successful swing against any reptile-classified monster — the reason every PvM build that runs dragons, drakes, lizardmen, snakes, or ophidians keeps a Reptile Slayer in the rotation.

What counts as a "Reptile" target

The Reptile Slayer tag matches the following monster groups:

Creature group Notable members
Dragons Dragons, Greater Dragons, Reptalons, Wyverns, Frost Dragons, Skeletal Dragons, Drakes
Lizards Lizardmen, Lizardman Mages, Reptiles
Snakes Giant Serpents, Coral Snakes, Lava Serpents
Ophidians All Ophidians — Avenger, Knight, Mage, Matriarch, Shaman, Apprentice
Sleeping Dragon Bosses with reptile classification
Hydras and similar Multi-headed reptilian bosses
Sea creatures Some sea serpents, leviathan-class reptiles

The classification is engine-internal — the player cannot generally see which monsters are tagged "Reptile" except by experimenting with a Reptile Slayer weapon (the canonical "is this Reptile?" test is just to swing at it).

Reptile Slayer vs. specific lesser slayers

For some Reptile-class monsters, a more specific lesser slayer also exists:

Specific lesser slayer Targets Reptile Slayer covers same?
Dragon Slayer Dragons + Greater Dragons Yes (Reptile Slayer = 2× same)
Snake Slayer Snakes + Lava Serpents Yes
Lizardman Slayer Lizardmen Yes
Ophidian Slayer All Ophidians Yes

Each lesser slayer also delivers 2× damage against its specific group. So Reptile Slayer (Super) and Dragon Slayer (Lesser) deliver the same 2× damage against a Greater Dragon — but the Super covers many more monster types. This is the canonical reason Super Slayers are preferred for general-purpose builds; Lesser Slayers are kept for specialised single-monster grinds.

Sources of Reptile Slayer weapons

Source Mechanism
Random loot drop Any monster can drop a Reptile-Slayer-tagged weapon
Champion Spawn drops Higher-tier champ rooms drop slayer-tagged weapons
Imbuing Reptile Slayer is an imbuable property — 1 intensity slot
Runic crafting Higher runic-tier rolls can produce Reptile Slayer-tagged items
Reforging Runic ingot rolls can land Reptile Slayer
Heritage Slayer instruments A specific slayer instrument can be crafted with Reptile Slayer for bardic builds

Reptile Slayer instrument (bardic build)

The Reptile Slayer Instrument is a parallel item — an instrument that grants the bardic skill check against reptile targets a 2× effectiveness in the Provocation, Discordance, or Peacemaking check. The mechanic mirrors weapon-side Reptile Slayer:

Effect On bard skill check
Effective Skill bonus +20% against matching reptile (this is the canonical slayer instrument bonus)
Range Standard bard range — 8 + (skill / 15) tiles
Stack with player skill Additive bonus — pushes ineffective bard skill into effective range

A 120 Music + 120 Provocation Bard with a Reptile Slayer instrument can reliably Provoke creatures up to 117 Barding Difficulty — pushing the Provoke target into the canonical end-game range (Yamandons, Dragons).

Imbuing Reptile Slayer

Property Max imbued intensity Resources
Reptile Slayer (weapon or instrument) 100% (Slayer is binary — present or absent) 5 Enchanted Essence + 10 Magic Residue + 1 Slayer-specific gem

The Imbuing menu offers Reptile Slayer as a single intensity choice — there is no "weak Reptile Slayer" intermediate tier; it's either present (full 2× effect) or not. The intensity cost is 1 of the 5 imbue slots.

Build implications

Build Reptile Slayer strategy
Sampire Reptile Slayer Halberd is the canonical "every dungeon" weapon
Pure Mage N/A — slayer doesn't apply to spell damage
Throwing Gargoyle Reptile Slayer Soul Glaive for ranged dragon-killing
Tamer Pet ignores slayer; Bard side may use Reptile Slayer instrument
Bard Reptile Slayer instrument essential for bardic dragon/wyvern grinds
Archer Reptile Slayer Bow + Reptile-tagged arrows for range matching

Spawn-locked Slayer Quivers

Quivers can also carry a Reptile Slayer property — when equipped alongside a matching slayer bow, the quiver's slayer-tag adds a percentage damage modifier layered on top of the weapon's 2× slayer (a small but additive bonus). This is the canonical reason quivers are not just utilitarian — a Reptile Slayer Quiver on an Archer paired with a Reptile Slayer Bow stacks the two for a small net damage uplift against reptile targets.

See also

  • Slayer — the system overview; full Lesser/Super slayer roster
  • Vanquishing — the rare "all monsters" slayer-equivalent enchantment
  • Damage Increase — the pre-resist multiplier the slayer 2× sits on top of
  • Base Damage — the weapon Min/Max the slayer multiplier applies to
  • Imbuing — the canonical way to apply Reptile Slayer to a weapon
  • Provocation — bardic skill that benefits from a Reptile Slayer instrument
  • Ophidians — a major Reptile Slayer target faction
  • Dragon — the canonical Reptile Slayer target
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Folios in the Codex incorporate material adapted from community-maintained Ultima Online wikis, used under the Creative Commons Attribution-ShareAlike 3.0 License. Synthesised, restructured, and rebranded by the Scribe.