Earthworm Jim is full of cool, absurd characters: Jim is an earthworm in a special suit, and is friends with Peter Puppy who transforms Hulk-style into a ferocious beast, but then you have antagonists like Bob the Killer Goldfish, Psy-Crow, Evil the Cat, and Major Mucus.
The original game was a 2D side-scrolling "run and gun" platformer with some bonus stages. In this sequel, you do have some of those platforming stages but the extra stages seem to have more focus. Even in the platforming stages, there can be different ideas like having to carry pigs and cows to a certain location in order to progress.
It is constantly changing what you are doing. You will be on a platform level, then bouncing dogs to Pete, then an isometric flying level, slowly moving as a blind cave salamander avoiding the sides of the level (meanwhile the music is Moonlight Sonata), then participating in a quiz. It's varied gameplay, but extremely quirky.
In the first game, you played a stage called "Andy Asteroids" multiple times throughout the game. This game has "Puppy Love" where you need to bounce puppies over to Peter. These stages seem to last a little long, given that you need to play multiple rounds each time.
The game can be pretty tough and there's definitely some really frustrating sections especially when it can be a little unclear what you have to do.
I think this game does better at differentiating background objects from the foreground which was a problem in the first game. The only unclear paths are to find the secrets, although some of these secret areas are required for the save system. In the "Password" menu, you can choose a level to start from which is only allowed if you have found the "Earth", "Worm" and "Jim" flags in that level.
Jim comes armed with a gun which can be aimed in all eight directions. Jim can also use himself as a whip which is a method of attacking. In the first game, his head was also used to grab and swing from hooks as well as gliding as he fell. In this sequel, you now have a parachute to glide, and a snot buddy for the hook-shot. There’s different gun pick-ups during the platforming levels but I felt they were underutilised.
You have a percentage health bar, and a limited number of lives. If you die, you can choose to continue. There are extra lives to find, and "atoms" can be collected to replenish your health. The GOG version seems to remember what flags you have collected for the “Password” system, but I did wonder if some of the original versions saved your progress at all.
I'm not sure if it is a DOSBox issue or the game, but I pressed Esc key with the intention of pausing, and it ended the game without confirming and a lot of progress was lost - so be careful!
Earthworm Jim does have some frustrating elements to it, but still remains fairly playable today. People considered it a classic back in the day when it was released, and it is fairly easy to see why. It's zany, well animated, and has varied game-play. I feel like it could do with a couple more traditional platforming levels though for more consistency and to give you more use out the extra gun types.