Took me way too long (backtracking, and mean "traps/one way streets"), but the rather minimal music was soothing and kept me going despite me getting lost like that one green alien who got confused by all the portals. 

The progression in terms of items (regular zapper, portal zapper, rope gun), and the new environments they made available, plus the water drain "wet-dry-land-lite" mechanic, felt straightforward and satisfying. I liked how the parts of the map that were interactive just blended in with the rest of the environment more or less seamlessly. 

I enjoyed the overall polish, such as the particle effects, the water's buoyancy, the scores shown when collecting coins & the sound effects, the great textbox effects (visual and in terms of audio), the eyeball chain-chomps' rope physics/behaviour, and the items' smooth animations. 

That one jump where I had to zap an eyeball enemy right after I had to use the rope gun by switching quickly to the zapper mid-air to avoid getting hit was fun platforming actually; it was also possible to take the eyeball out from below with the zapper if I acted fast enough afterwards with the rope. 

The end was a bit unexpected, maybe I just didn't get it. Sometimes, it was not clear to me whether a jump was supposed to be impossible or not, as some of them were quite tight. 

Great little game, and extra impressive considering its time and platform constraints.