Single player, by 
Azazilisland starts strong (as shown in the screenshot), placing you in the middle of the level with a bunch of stuff going on in every direction. This is a very non-linear level, so you can go in any direction and still make progress, assuming progress is defined by gradually removing all enemies and pickups from the level. There are a handful of spots in the level that are actually necessary to visit, in order to hit certain trigger zones, but for the most part there’s not a lot distinguishing those spots from any other possible destination, so your best strategy is just to go everywhere and do everything. If there’s an enemy near you, you haven’t gone that direction yet, so give it a try.
There seems to be a bit of an intended order for you to visit the trigger zone spots, in that certain of them are initially locked off by trigger scenery blocks that get removed by others. Nothing about this order is explained anywhere in the level, and nor is the end area made very explicit, and yet somehow I found myself visiting everything in exactly the right order (and guessing where the end area was). I don’t know if this is coincidence or level design genius but either way it’s hard to complain about.
This is, then, a level all about exploration, and thankfully there’s a decent variety in areas contained within the level: you’re not just in a maze of twisty little passages, all alike. The most obvious example is that the entire bottom section is a sandy beach, but the thin wooden platforms are more or less common in different parts of the level, and there are a handful of other landmarks to help you figure out where you are. Additionally, the level is very easy to explore (if you’re willing to do the occasional uppercut/double jump onto a higher wooden platform), preferring lots of small blocks over long tunnels, so it’s always possible to change direction and wander until you find somewhere genuinely new. The only real slipups on the explorability fronts are certain tiles which look like they should be vines but are in fact fully solid, therefore preventing vertical movement between areas.
Indeed, the level is so navigable that there’s even a witch enemy toward the top of the level, with Eva placed a little farther down, more in the middle. If you forget where she is, it’s possible to fall all the way down to the bottom of the level and eventually climb back up to find her again (provided you don’t die along the way). I’m not sure how I feel about the witch’s inclusion overall, but I appreciate that the level makes sure you can get back up to her as a frog… but not much farther up than that.
Besides the one witch, there’s a respectably-sized menagerie of enemies that seem appropriate to the tileset, all managing to pose the occasional, yet never outsized, thread. The level also boasts a solid, yet never excessive, number of carrots and ammo pickups to make your battles that much easier. And ultimately its success lives and dies on the question of how much you enjoy walking around and shooting normal JJ2 enemies, because it gives you a whole lot of opportunities to do that, without any obvious flaws but without any enormous innovation or variety… and there’s nothing wrong with that.