For my next NES Obscurity Quicky, I'm going to take a look at the Spooky-Old-House-'em-up that is...Dr. Chaos!
To start off with, your jumping and fighting mechanics are a little dodgy; not Ghost n' Goblins stiff/jerky, but not Metroid levels of solid, either
Furthermore, lots of people just think this is a game where you wander around some useless hallways, stabbing quickly-respawning rats and bats with a knife...
...only occasionally breaking the monotony by going into one of the dozens of rooms and doing Goonies II-like first-person "Open or Hit then Get" interface to collect bullets...
...just so you can then SHOOT the quickly-respawning rats and bats.
Oh, and the only other thing that's pretty easy to discover without a FAQ: if you turn around too many times in the same room...
Somethin' big chases you out of the room, and proceeds to wail the crap out of you!
But Dr. Chaos is
so much quite a bit more than that: there are a large number of rooms that have a "warp zone" or something...in these, you can use the GO command on a random cabinet/closet/drawer/window..
...and then you're warped to one of the EXCITING SUB-LEVELS!
These levels function kind of like side-scrolling (linear) dungeons: they're a self-contained, involve some platforming challenges etc, and most importantly...
End in a boss fight, which rewards you with an item, PLUS a piece of the last-level-McGuffin device, PLUS a password!!
...More Bad News
It's not all puppies and lollypops, though -- after you beat the boss, you STILL have to walk all the way back to the beginning of the sub-level (or I guess you can die and start back with less bullets etc).
Also, you know the first item you get from the first boss (pictured above)?
It's a SUB-LEVEL DETECTOR...which blinks when you're facing a wall which contains a cabinet/drawer/window which is a gate to a sub-level. So from now on all you have to do is watch for the blinking, then move the pointer over every object and click "GO" (after opening some of them), and you'll get to every sub-level.
If only you'd been able to get that item WITHOUT going into a sub-level -- perhaps by exploring many of the normal rooms, you'd find it, then its blinking clues would tell you that SOMETHING'S up.
If they'd taken that approach, a lot more people would have realized this game offers a lot more depth than rat-stabbing.
But there's some more Good Points, too!
Some of the later items give you extra powers -- sadly, only usable in sub-levels -- but still, there's some sub-levels you can't explore until you get the spring shoes, or the scuba gear, etc.
I think it's a shame that Dr. Chaos is lost to obscurity, when there's a smidgen of Metroid-Vania fun to be had in this 1988 game. But as I've said, it only has itself to blame for hiding its fun.
— carlmarksguy, 2012-08-03