Very unusual monster features

This table may be handy during creation of the unique specimens of some monsters. Roll 1d12:

1. Crystal body. -2 AC, +11 HP
2. Toxic Blood.
3. Electricity instead of blood. Damages its opponent if wounded with metal / natural weapon.
4. Multi-limbed. 1d4 additional attacks per round (determined each round!).
5. Explodes when killed. 1d10+3 damage in 2d6m radius.
6. Venomous Kiss.
7. Incorporeal. -1 AC, -1 damage dealt (to minimum 1), all damage dealt counts as magical, damaged only by magic (weapons, spells or abilities).
8. Splits when damaged. Only 1+2 HD, if not killed with one hit, it splits into two separate monsters.
9. Golden body. -1 AC, +1 damage, +2 HD, may be worth a fortune.
10. Opens a portal when killed. When the monster is slain, magical portal opens and spits out more monsters (another roll for wandering monsters is needed).
11. Robotic. -1 AC, +1 damage die (lazors, force swords etc.), 1 HP regenerated / round.
12. Hybrid. Roll for another wandering monster and mix the features of these two (incl. AC, HD etc.).

Additional table that may be used to determine why this particular monster was so different. Roll 1d6:

1. Result of a magical experiment of some kind.
2. Gift / curse of gods.
3. Effect of a powerful spell (may be dispelled).
4. Extremely rare mutation (imagine the mutagenic substance that turns flesh into a machine!).
5. Extra-planar monster, just resembling some monster known in this world.
6. Avatar / messenger of some minor deity (killing it may have unexpected aftermath!)