If you polymorph into a naturally tunneling monster you will gain the ability to tunnel without a pick. You will still be able to use a pick, provided your new form has hands and is strong enough to carry it. Rock moles, for instance, generally cannot even lift a pick-axe. Your digging is handled separately however, even while in polyform.
When a monster tunnels through solid rock (the blank areas surrounding most of the dungeon), there is a 1/3 chance of some waste being produced. 1/4 of the time this waste will be a boulder, the rest of the time it will be a single rock. No message is produced.
Monsters capable of tunneling
Without a pick/axe
With a pick/axe
- Archeologist related:
- You hear crashing rock
- Produced 1/5 of the time when a monster tunnels through a rock wall
Monsters that can tunnel have the M1_TUNNEL monster attribute. Monsters that require picks and axes also have the M1_NEEDPICK monster attribute in addition to M1_TUNNEL. No monster in vanilla NetHack has M1_NEEDPICK but NOT M1_TUNNEL.
- m_move in monmove.c -- decides when and if monsters can and will tunnel.
- mdig_tunnel in dig.c -- performs the tunneling. Called by m_move.