This game's about a 4/10. I enjoyed playing it, but I don't plan on playing it again or trying to get the Easter eggs.
Story: A rather generic "save girl from cult sacrifice + demons" plot. Gorefield wasn't as prevalent in this game as I expected, besides the protagonist being a lasagna boy named Jon, the Chapter 1 chase scene, the [spoiler]Mr. Chesterfield boss fight[/spoiler], and [spoiler]the "I'm Sorry Jon" joke at the end of Chapter 6 [/spoiler]. The references didn't have to overpower the overall plot, and I get the need to avoid copyright issues, but I feel like a few more elements would have added some character to the game. Maybe rename the girl Eliza (Liz), or have that one cultist's name be Lima (Lyman) instead of Grima.
Gameplay: The platforming is typical, but fun, and the standard controls behave consistently (besides the fact that B manages both sprinting and lighting/firing, and I can allow that considering the limits of the GameBoy). The level design is solid, too; I felt like the game put me through a variety of different situations. However, there are a lot of rough edges throughout.
-Certain basic tasks take too long. Turning the portcullis wheels takes about 10-15 seconds of sustained button mashing in the early chapters, and the piston heads on the gears usually need to be shot about 10 times before breaking.
-Similarly, some sections are too long. The parapet jumping section in Chapter 3 was one such section, as besides the blackout/lightning there wasn't much in the way of challenge. Wait for lightning to strike, jump, repeat x 20. It made thematic sense for the three [spoiler]rising lava sections at the end of Chapter 6[/spoiler] to be this way, considering you're [spoiler]heroically carrying an injured Gilda out of the bowels of the Earth and away from the castle[/spoiler], but I still think the third was a bit much, essentially since it was mostly switchbacks.
-The fake perspective makes the stealth sections a bit weird, as the "perspectived" sections of the pillars don't actually hide Jon, only the flat parts. The stealth is very touchy as well, to the point that if even a single pixel of Jon is outside the pillar you're visible.
-The rolling barrels are spaced randomly. Since getting hit twice in a row kills Jon, your ability to survive a mistake becomes random as well. This isn't necessarily a problem on its own, but some sections don't let you see the barrels well in advance, such as when they drop from the ceiling or descend a ramp the camera isn't facing yet. You have to pick a time that *looks* safe and hope you don't get blindsided.
-The minecart sections are janky. On level surfaces, the cart accelerates slowly, so it can get stuck in shallow valleys. (The section automatically resets when the cart comes to a complete stop, which is the only mechanic preventing this from being a softlock.) Jumps are difficult and heavily rotation-dependent. Sometimes you'll make it, sometimes you'll fall just short, sometimes you'll land but flip over because a wheel snagged the edge of the track, and sometimes you'll find yourself *underneath* the track, hanging only by the wheels that got wedged on top of it. The worst examples of this mechanic, [spoiler]the first three sections of Chapter 7[/spoiler], resemble Line Rider courses in their obtuse track placement, sporting near-vertical jumps and walls that require you to rotate vertically so you don't crash on them. Your lives get reset at the start of each of those sections, and boy is that feature necessary. Be ready to hear a lot of Wilhelm screams.
-Bosses are okay. A bit too much head-banging for my taste, though. In terms of story, [spoiler]Mr. Chesterfield[/spoiler] felt like it should have been the final boss, and [spoiler]the rising lava section[/spoiler] should have been the last platforming section, with [spoiler]Chapter 7[/spoiler] as a bonus level for a golden ending. Mechanically, [spoiler]Molech[/spoiler] was still a better final boss, though [spoiler]going back and forth between those hands got pretty obnoxious[/spoiler].
Visuals: The best part of the game, hands-down. The portraits, character & enemy designs, animations, cutscenes, etc. are very strong. I especially liked the parallax lighting system, and the spiral staircase animation. The level backgrounds and elements are the weakest link here. They don't look bad, but they're generic. Also, the fake perspective of the stairs gets jarring when there are two sets facing opposite directions.
Music: Bare-bones. The tracks are all about 20-30 seconds long. They match the mood of the game, but besides that they're nothing special. The audio quality is a bit clipped, but that might just be how GameBoy sounds.
Nitpick:
-"sacrifice" is misspelled in the [spoiler]pre-Mr. Chesterfield boss cutscene[/spoiler]
