Add the 3 unused weapon sprites as default weapons
The three unused, original weapon sprites - laser, Sheep-on-a-rope and black gun - would be great additions of new weapons with unique mechanics.
Add them as default weapons.
My proposals on the weapons' mechanics:
a two-shot weapon with low damage (~15hp);
fires a laser beam for a certain amount of time (~10sec);
can be aimed during firing (like the flamethrower);
the beam will cut through terrain and create a tunnel too small for worms but big enough for animals and other projectiles;
a worm hit by the beam will get nudged slightly (like the prod);
the laser beam can be reflected off terrain on low angles, but damage and burning through terrain will be reduced;
oil barrels and weapon crates will heat up and explode (like flames do).
Bring it back!
--oldschool, like in W:DC with the worm firing a rope and the suddenly appearing.
--new school (consistent with other sheep-type wepaons), where the worm drops a standard sheep and on the second press of the button the rope fires from the sheep, possibly straight up (the also supersheep launches straight up).
2) Black gun:
Use it as an "Gamma ray gun", as previously suggested by Run in his Worms Unlimited proposal.
A two shot weapon that can fire through terrain;
Damage maybe lower to the shotgun;
oil barrels and weapon crates should heat up due to the high energy gamma rays;
radiation sickness (poison effect).
I don’t feel that adding hard-coded gameplay mechanics elements, such as weapons, is part of our goal. This might happen when support for custom weapons (a-la Fiddler) will be added.
Edit: maybe I should make it clear that just because someone drew these sprites, it’s still not trivial to add them as new weapons. They need to be converted, palletized, added to the graphics archives and redistributed, not to mention all the game engine changes required to make these work.
The custom weapon support sounds awesome! I know there's wormkit + project x but it freezes way too much.