These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Also counts as Mood Whiplash with the sign gag: "You must be THIS TALL to survive the dungeon."
The second scene is worse. Mickey struggling to swim upwards even though he's chained up, noticeably exhaling when he can't hold his breath, and finally fainting. The air bubbles that escapes his mouth form his famous head silhouette.
A gag with tombstones for the trio in Pete's lair, each one with a carved skull shaped like the character's heads on top of each one.