You should be able to create a sack from a crocodile corpse, similar to how you can turn it into a pair of low boots.

As a Peter Pan reference, produce “You hear a faint ticking noise” occasionally and prior to the normal output when stethoscoping a crocodile. Alternatively, produce this noise very rarely when a crocodile is anywhere on the level or near the player. Possibly only if the crocodile’s monster ID number matches a rare condition, like being a multiple of 100.

New artifact The Captain’s Hook, artifact grappling hook that never fails to do what you want it to do and has zero chance of hooking yourself, regardless of skill. Deals double damage to crocodiles.

Polymorphing a crocodile corpse makes fireproof water walking boots instead of fireproof low boots.