OSRS Boss Gear & Inventories

Phantom Muspah

Combat level 741 · 850 hitpoints

A three-phase prayer-switching boss and the source of the Venator bow. Its defences flip between forms. The form that attacks with ranged is soft to ranged, and the form that comes into melee range is soft to magic, so it is fought most effectively with Magic and Ranged together.

Requirements

• Secrets of the North
• ~80+ combat stats
• 70+ Prayer recommended

Pointers

• Style by form: RANGED form → hit it with ranged. MELEE form → hit it with magic. That flip is where most of the damage difference comes from.
• Shielded form: a crossbow with SAPPHIRE BOLTS (e) is strongly recommended. The enchant drains its shield fastest.
• Phase 1: it swaps between Ranged and Magic every few attacks. Watch the projectile colour and flick prayers. This is the entire skill of the fight.
• Phase 2 (shielded): it becomes immune to your attacks until you break the shield; spikes erupt from the ground, keep moving.
• Phase 3: it charges to melee range. Protect from Melee and step out of the spike lines.
• It drains prayer aggressively. Bring more restores than you think you need.
• Salve amulet does nothing here. It is not undead.

What the sim brings here

Every worn slot and every inventory row below is the combat simulation's own output, at the style it ranks fastest for each account tier. Each line carries the channel that chose it: sim means the model solved it, and inherited means the value came through from the hand-authored loadout the solver starts from. Riding through a generator does not make a value derived, so those are marked rather than presented as the model's answer. A line marked unattributed carries a channel the model's own vocabulary no longer declares, so no word is put on it at all rather than one being read off the channel's spelling. Where the model has not answered a row, its own refusal is printed instead; where it has answered a row it doubts, the answer is printed with the doubt attached rather than withheld.

What each of those badges means

• derived:ascent (sim): an accepted coordinate-ascent move: betterThan() preferred this candidate over the incumbent under the row objective and band. The weapon+ammo+shield pairing and the crystal set arrive here too, because both are offered to the same acceptance test.
• derived:composed (sim): balanceInventory() sized this row from the derived supply menu. The menu enumerates CONSUMABLES and narrows by style, tier and price; it is not the authored bag.
• derived:empty (sim): the finished loadout leaves this slot EMPTY, and that is an ANSWER rather than a gap: a two-handed weapon forfeits the shield and a weapon that stores its own ammunition frees the ammo slot. Recorded so a null slot is never read as unprovenanced.
• derived:seedWeapon (sim): the weapon the ascent BEGAN from, taken off the dps-ranked weapon shortlist, or the forced weapon of a multi-start seed. Never off a start loadout.
• derived:travel (sim): travelPlan(): the way IN, ranked out of the derived transport graph against this account's own unlocks, rather than copied from whatever a human typed. The way OUT is a separate channel (`ruled:escape`) because it is a typed choice, not a ranking.
• derived:voidSeed (sim): the Void set offered assembled, because an all-or-nothing set effect pays nothing until four slots are right and every single step toward it is a strict loss. The pieces come from VOID_SET in combat.js, the same names its own predicate tests.
• ruled:escape (ruled): escapeLeg(): the way OUT, taken from the typed per-tier table ESCAPE_PLAN and judged against the account, with nothing substituted and no fallback ladder. The ACCOUNT CHECK is a derivation; the CHOICE of item is not, so this is not a `derived:` channel. ESCAPE_PLAN carries no attributedTo field (PROVENANCE_BACKLOG: silent-and-unattributed), so this channel does not claim one either.

Phantom Muspah strategies on the OSRS Wiki