GameWTFs.com

"...you keep jumping if you hold the jump button down. It's not a major thing, because really, how often do you hold down the button after you've jumped, but it just feels wrong. I'm sure there are other platform games where you'll jump every time your feet touch solid ground if you hold down the button, but I can't think of any off the top of my head and the phenomenon definitely contributes to the feeling of slightly wonky other-ness that only unlicensed games seem to possess."

"This is all my doing and I'm proud of it."

1. one height: does your character jump the same height, no matter how long you press the jump? If so, you can just tap the jump button to jump, and you probably won't hold the button down too long and accidentally jump again.
2. few pits: are there not too many bottomless pits to jump over? If there's not that many places you have to worry about falling to your death, auto-jumping probably isn't as big a deal.
3. "up" arrow: is jumping triggered by pressing "Up" on the D-Pad, rather than the A or B button? If so, it's less platformer-like, so repeated jumping can be more easily forgiven.
4. jump extras: do you have extra powers to tweak your basic jumping/falling? If so, maybe you can assist your platforming with those abilities.
5. auto-attack: are some of your attacks fully automatic as well? If so, maybe the programmers were just incompetent in general. As Zeke from Totally Rad might say, "give 'em a break, dude!"

Conan	one height Y	few pits N	up arrow Y	jump extras Y	auto attack Y	4 / 5 A hoppin', skeleton-kickin', chimera-punchin' romp for our favorite Hyperborian (or a stick figure facsimile thereof), this game proves that having a high Mitigating Factor score doesn't make for a fun experience. This game is unlike most NES platformers because its a port of a computer game: they somehow needed the A and B buttons for your separate "punch" and "kick" attacks...and not only does Up on the d-pad make you jump, but Down on the d-pad makes you do a standing leap for greater horizontal distance. Unfortunately this game fails the most important mitigating factor: your ungainly barbarian has to do lots of platforming over bottomless pits.
Quattro Adventure: Linus Spacehead	one height Y	few pits N	up arrow Y	jump extras Y*	auto attack N**	2.5 / 5 The unlicensed Quattro Adventure has 4 separate not-very-good games, and one of those games features Linus Spacehead and his constant jumping. Let's dig in to the caviats! * = In the first level, you spend most of your time riding on temporary bubbles...and oddly enough, if you land on a bubble you DON'T keep auto-jumping even if you hold the jump button down ** = Linus has NO attack. This is par for the course for 75% of Quattro Adventure: even Boomerang Kid takes a page from Mighty Bomb Jack's book (if that book is titled, "how to be named after a weapon, then spend the game just GATHERING those weapons and never USING them").
Solstice	one height Y	few pits Y	up arrow N	jump extras Y*	auto attack N**	2.5 / 5 This isometric bouncing-wizard puzzler is jumping-heavy, but at least there's not many bottomless pits...there's quite a few SPIKY INSTANT-KILL pits, but I guess that's splitting (impaling?) hairs. It's just unfortunate that precision jumping is difficult because the isometric view makes it very hard to see where you are, exactly. * = situational extra-jumping stuff: most of the game's puzzles are based around picking up/absorbing(?) portable blocks, then dropping them while in mid-jump so you can do a SECOND jump off the newly-dropped block. ** = your only offensive maneuvers are spells, which you cast through a submenu...just like in Advanced Dungeons & Dragons: Heroes of the Lance!
Legend of Kage	one height N	few pits Y	up arrow Y	jump extras Y*	auto attack N	2.5 / 5 Kage might have the biggest vertical leap of any video game character on the NES: if you press and hold the UP arrow in the outdoor levels, Kage goes so high the screen will scroll upwards before he begins his descent. * = situationally, you can climb freely trees or land on branches to get even more air.
Dash Galaxy in the Alien Asylum	one height N	few pits Y	up arrow Y	jump extras Y*	auto attack N**	2.5 / 5 This might win the award for "worst use of a great video game name." Dash Galaxy plays like an early Prince of Persia, except with the big-vertical/little-horizontal jumping power of Ice Climber's florescently-dressed Inuits. It's also a really bad example of the Scoot or Die school of enemy design: they're not big enemies, but they ARE very slow. In fact, EVERYTHING in this game moves at a snails pace, and if the enemies stroll through you, they'll quickly drain Dash's energy and send him from the Alien Asylum to a Multidimensional Morgue. * = situationally -- a lot of the game involves bouncing repeatedly on trampolines to get greater height. ** = you have no direct attack; you can sometimes collect bombs...but if you blow them up WITHOUT the detonators (sold separately), you're just as likely to kill yourself as the enemies. Evidently Dashing Mr. Galaxy has no better combat training than kids playing with firecrackers.
Fox's Peter Pan and The Pirates	one height N	few pits N	up arrow N	jump extras Y	auto attack Y	2 / 5 Despite being one of T*HQ's proud creations, this game definitely has the look and feel of an unlicensed game. There's the loose gathering/losing of hitpoints, the way the level blinks black then immediately starts again when you lose a life (without giving you any specific message acknowledging it happened), the cage that falls on you and SOMETIMES takes you to a bonus-round, and turbo-attacking/turbo-jumping galore. The most noteworthy feature is that you also have a finite amount of "fairy dust", which allows you to just hold the "UP" button to fly whenever you want. If your reflexes are quick enough (and you have enough fairy dust left), you can save yourself from falling off the screen after you miss a jump.
Spider-Man: Return of the Sinister Six	one height N	few pits Y	up arrow N	jump extras Y	auto attack N	2 / 5 Aside from the hilarious title screen (which suffers from trying to show too many different characters at the same time, and the NES's limited pixel-size/color palette just isn't up to the task), there's a lot of good pixel art in the game's between-level pictures. What's not so good is the flighty controls. There's the repeated spidey-jumping of course, but the B button works a little wonkily, too: if you press "B" once, you Punch. But if you press "B" rapidly (like you're trying to repeatedly punch), you'll instead launch a big, bold radioactive-spider-powered jump-kick. However, if you hold "B", you stick your fist out and hold it there, like a hitchhiker with a bashful thumb. Sadly, your enemies will not choose to strike their face against your extended hand, leading me to believe this "high five pose Spidey" is, in fact, a glitch. You also get to shoot some diagonal swingin'-webs during your jumps, which can latch on to some of the platforms/background to let you swing back and forth. Unfortunately, unlike a Super Nintendo Spider-platformer I could name, you can't jump at the apex of your swings to slingshot yourself forwards like Tarzan or Bionic Commando: once you let go of your swinging web, you fall straight downwards. However in rare occasions where you can get enough space (like in Level 2, where there's a pit that's impossible to get out of through normal means), you can choose to rock back and forth by your webbing enough that you'll spin up onto the platform you're dangling from; exactly like riding a playground swing until you loop over the top.
Wizards & Warriors	one height N	few pits Y	up arrow N	jump extras N	auto attack N	1 / 5 This entire NES trilogy has the same weird bouncy-knight-in-a-very-tall-level mechanics, where your primary attack is to nudge enemies with the sword jutting out of your torso during your incredibly vertical-centered jumping. Fortunately, there's not many places where you have to leap over pits; usually a missed jump means you have to climb upwards again, or at worst you fall into energy-sapping lava.
Ironsword: Wizards & Warriors II	one height N	few pits Y	up arrow N	jump extras N	auto attack N	1 / 5 Jumping-wise, this game is similar to Wizards & Warriors...though it has a few more bottomless pits, and some very annoying "sloped hills that you slide helplessly to the bottom of, if you set foot on them."
Wizards & Warriors III: Kuros: Visions of Power	one height N	few pits Y	up arrow N	jump extras N	auto attack N	1 / 5 This supposedly has more RPG-ish elements (I haven't played much of it), but the fact that you start in a town which is more vertically-built than the Ewok Village leads me to believe we'll be seeing more of the same jumping mechanics here.
Castlequest	one height N	few pits Y	up arrow N	jump extras N	auto attack N*	1 / 5 The Wizards & Warriors games are proof positive that fully-automatic-jumping games don't necessarily have to be bad...but this game is bad. It's basically built to make unwinable situations incredibly likely: there are more color-coded doors than there are the matching color-coded keys, so if you open too many doors that don't happen to be useful...might as well press "reset". Helpfully, it raises numerous red flags early on that you might as well stop playing: you start with fifty lives, your character flails around like a baby with a loaded diaper when you die, and of course there's the fully-automatic-jumping powers. In an extra display of lazy programming, your jump's apex/decline time doesn't get interrupted when you bang your head on a ceiling: sure, the ceiling stops you from moving UPWARDS, but in most games, if you could jump three "blocks" upwards, but hit a ceiling after two "blocks", you immediately begin falling. Not so in Castlequest! Here you continue to mash your head against the low ceiling for the same amount of time it would have taken you to travel a further "block" upwards, then to fall that "block" downwards...so you festive hat is pressed against the ceiling for an uncomfortably long time. * = it also has really lousy attack controls: you can't just press "B" to stab, you have to press B and left or right to stab. Even Heroes of the Lance isn't that cruel with their basic attack (you just have to press weird chords of B/D-pad to attack upwards or downwards)!
Amagon	one height N	few pits N	up arrow N	jump extras N	auto attack N	0 / 5 Basically a loser on all fronts, this is a game where you have to do normal platforming while you're usually playing as the one-hit-and-dead Amagon. Add top that, you're doing your platform-leaping with the Turbo Jumping to remember. The only thing that helps with your jumping is that, when you "hulk up" into Megagon, he jumps almost twice as high/far as Amagon. (in case you're interested, here's some more reflections on playing Amagon)