Is there actually a secret HAL room?

Question

I hear tell that there is a secret HAL room in this game. A room that has the HAL name in star blocks, as well as a set of Copy Essences.

This is supplemented by the ending credits, which includes a screenshot of the room in all its glory. As every other screenshot in the credits sequence is actual game footage, it seems fair to assume this is the case here as well.

Does this room truly exist, and if so, how do I find it?

Answer

That room is in 1-4. Go to the end of the first room in 1-4, go as far to the right as possible, past the door. Then go backtrack a bit, you'll soon find a new door. Now enjoy some cool stuff.

The other one is in 6-5. It isn't as hidden as the first one, but you have to pay attention or you'll miss it. Watch for ninjas and a hamburger at the end of the third screen, then press on up past the belts for an opening.

There's other secret rooms, but theses are the only two HAL rooms I've found.

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