Polymorph

Version 0.13: This article may not be up to date for the latest stable release of Crawl.

Polymorph
Level	4
School1	Transmutation
School2	Hexes
Source(s)	Book of Transfigurations
Casting noise	3
Spell noise	0

This spell randomly alters the form of another creature.

Polymorph is a Transmutations spell which, if used on a natural, holy, demonic, or plant monster, will transmute it into another monster of the same category, usually with the same or slightly higher HD. Some chaotic creatures are special cases: ugly things simply change their color, while shapeshifters and glowing shapeshifters will heal some HP and change form. The resulting monster can't be a unique, undead, pandemonium lord, statue, derived monster (those with different values for their monster type and species fields: non-base orcs, non-base draconians, etc), a monster that doesn't provide any experience, or a monster that belongs to the no poly category.

If Polymorph is used by an enemy on a player who fails to resist, the player will suffer a temporary bad form transformation. Mutation resistance is useless against this, but magic resistance and worshiping Zin may protect you.

Followers of Zin incur a piety loss and a penance if they cast this spell.

Similar effects can be achieved with a wand of polymorph, the attack of a chaos weapon, the Plutonium Sword, and some Transmutations miscast effects.

Strategy

Good Targets

This is a partial list of good targets for spells, wands or clouds of polymorph other - that is, monsters which are unlikely to become more powerful when polymorphed, i.e. monsters which are low-HD, high-threat.

• Electric eel - They'll turn into a less dangerous flying or water-capable creature.
• Red wasps and yellow wasps - If you lack poison resistance these can be very nasty.
• Moth of Wrath - They can turn a crowd of weaklings into a berserk mob.
• Boggarts (and other low-HD summoners) - Although fragile, summoners can bring lethal reinforcements into play. Fortunately they have low enough HD that the polymorph results are usually pretty pathetic.
• Jelly - Polymorphing is an effective means of avoiding their corrosive attacks.
• Harpy - An option if you have issues dealing with very fast monsters.
• Oklob plant - Usually turns into a wandering mushroom.
• Sigmund (and other well-armed uniques) - If he turns into anything but a humanoid, his branded scythe, spells, and wands will be useless.

Bad Targets

These are monsters that are actually considerably less threatening than monsters of similar or slightly higher HD.

• Hydra - These often become storm dragons or guardian serpents. Even if you have problems with hydras, these alternatives are worse.
• Slugs - They have very high HD. An elephant slug has the same HD as a titan. The results will not be pretty.
• Adders or other inoffensive creatures - you'd really rather have a boggart?
• Worms - They may hit hard early on, but they're slow and you'll soon outgrow them. But they do have fairly high HD, and a human hits harder and is much faster.
• Slime creatures - A single one can turn into a giant orange brain or a storm dragon. Larger versions can turn into multiple such creatures.
• Grinder - He has unusually high HD for such an early unique, and many of potential polymorph forms are quite dangerous, up to some tier-2 demons. Grinder the hellion or Grinder the tormenter is much worse than Grinder.
• Mennas - High HD and being holy give him a near guaranteed chance of turning into an extremely dangerous pearl dragon. Worshipers of good gods may want this, as a pearl dragon hide is a very desirable find, and the dragon's holy breath will deal significantly less damage to them. Worshipers of evil gods, demonspawn, and undead characters will probably want to avoid this.

History

In 0.14 it will become a monster-only spell.

Prior to 0.12, this spell was called Polymorph Other. When used on the player by a monster, it had the same effects as Malmutate.