Here is a list of all the bad mutations you can acquire. Although some may have situational uses, they are at best mixed blessings. Any of these can be acquired through any source of bad mutations.
Grants a chance of going berserk every time you attack. Chance of berserking rises with rank (1%, 3%, 9%), while chance of passing out decreases. Clarity negates it. Often referred to as "berserkitis".
| 1. You tend to lose your temper in combat.|
2. You often lose your temper in combat.
3. You have an uncontrollable temper.
Reduces AC provided by your body armour by half its base AC. Does not stack with the effects of Jiyva's Pseudopods mutation. Does not affect AC from any other source (i.e. other equipment, the protection ego, mutations, etc.), and bonus AC from your Armour skill is still calculated based on the armour's full base AC. Nagas and Centaurs start with this mutation. Races that cannot wear armour (draconians, felids, and octopodes) get a unique description.
| Can wear armour: Armour fits poorly on your unusually shaped body.|
Cannot wear armour: Your body is misshapen.
Causes you to shout periodically, as though you'd pressed the "!" key. Higher ranks mean more shouting and also makes your shouts louder.
| 1. You occasionally shout uncontrollably.|
2. You sometimes yell uncontrollably.
3. You frequently scream uncontrollably.
Slows your movement speed by multiplying your current speed score by 1.2 each rank. Does not affect your alternate forms. Nagas start at rank 2.
| 1. You cover ground slowly.|
2. You cover ground very slowly.
3. You cover ground extremely slowly.
Grants teleportitis, similar to a ring of teleportation. Higher ranks increase frequency and teleport range; level 1 only teleports over short distances while level 2 can go farther and level 3 can be anywhere in the level. An amulet of stasis negates it and other teleportation, while teleport control allows it to be controlled at the cost of glow.
| 1. Space occasionally distorts in your vicinity.|
2. Space sometimes distorts in your vicinity.
3. Space frequently distorts in your vicinity.
Grants a cumulative 20% chance to fail reading a book or scroll per rank. Any rank disables passive scanning for traps.
| 1. Your vision is a little blurry.|
2. Your vision is quite blurry.
3. Your vision is extremely blurry.
Each rank increases the nutrition gained from vegetation while reducing that of meat, including chunks. Rank 3 prohibits eating any meat. Centaurs start at rank 1, and Spriggans start at rank 3. This mutation is mutually exclusive with Carnivorous.
| 1. You digest meat inefficiently.|
2. You digest meat very inefficiently.
3. You are a herbivore.
| 1. You have a fast metabolism.|
2. You have a very fast metabolism.
3. Your metabolism is lightning-fast.
Causes periodic, temporary stat loss. Higher rank increases frequency. A ring of sustain abilities will negate this.
Natural recovery from stat loss tends to keep rank 1 in check. Ranks 2 and 3 will eventually kill you via stat death if allowed to progress unchecked.
| 1. Your body is slowly deteriorating.|
2. Your body is deteriorating.
3. Your body is rapidly deteriorating.
Each rank reduces max HP by 10%. This mutation is mutually exclusive with Robust.
| 1. You are frail.|
2. You are very frail.
3. You are extremely frail.
Each rank reduces max MP by 10%. This mutation is mutually exclusive with High MP.
| 1. Your magical capacity is low.|
2. Your magical capacity is very low.
3. Your magical capacity is extremely low.
Gives you -2 to an attribute per rank, up to -4 for each. Each of these mutations is mutually exclusive with its Improved Attribute counterpart. (Coded in-game as "Weak", "Dopey", and "Clumsy" for STR, INT, and DEX, respectively.)
| You are [very] weak.|
You are [very] dopey.
You are [very] clumsy.
Each level of this mutation decreases your regeneration rate by one third. This effect also affects the recovery rate of stat loss. At level 3, you will be unable the recover HP or attributes naturally. Ghouls start at rank 1, Deep Dwarves start at rank 3. This mutation is mutually exclusive with Regeneration.
| 1. You heal slowly.|
2. You heal very slowly.
3. You do not heal naturally.