Another silly idea for cheap monsters. I've been using it in some pirate games, I'll probably use it in a Pulp game too.
Early in the game, some of the players are told (in a pirate inn) that "Il faut craindre le Big Horneau" ("The Big Horneau must be feared"). This does not mean anything, so they believed it could be the name of a ship, etc.
Some time before the game I had gathered some (real) sea snails empty shells
In the game the sea snail shells were placed on a very far beach. They just look as dead sea snail shells, but
Characteristics:
- When characters walk on the beach, after some time the giant sea snails slowly turn towards the nearest characters; and the next game turn, they begin to move slowly.
- I give them 4 cm move per game turn. They move very slowly but nothing can stop them. They kill humans and animals if they can reach them.
- Melee weapons and muskets have no effect. They can be destroyed by placing a grenade or a powder barrel, just in front of them when they advance (a dangerous thing to do), or by cannon balls (1-3 hull points depending on their size, if your rules include hull damage points for the ships). Modern firearms could be more effective.
They may be there for natural reasons, or someone could have brought them a very long time ago (when they were very young and small) to guard a treasure or for some reason.
Characteristics and names can be adapted to the scenarios etc. I call them "Big Horneaux" it's a joke because "bigorneau" is a French name for sea snails :) In a 19th-20th century Pulp game I'll probably tell that they have been studied by a Pr. Panzerbülow and call them "panzerbülows" ("bulot" is a French name for a sea snail species, these shells are actually "bulot" shells).
In more modern games, I suppose that destroying them could raise difficulties with local authorities or green activists, as these giant animals certainly are an endangered species :)