The Binding of Isaac: Rebirth

the Super Meat Boy one (I just cannot get four Horsemen in a row...)

The Super Meat Boy and Bandage Girl achievements are stupid right now. The Book of Revelations guarantees a Horseman spawn on that floor (if you haven't fought him yet I believe), however using it in the Utero/Womb gives you Conquest instead of Death, which makes it nearly impossible to get Death unless you're just plain lucky. I think I've fought Death at most twice so far as a regular boss. I also remember resetting all the time in the original game for getting Famine on floor one...and now I can't get him on one or two when I want him to spawn. Add to this the fact that you can have 3 of one and then get the other one from the fourth horseman. It's just plain silly right now. I can see myself never getting those achievements simply because of this in its current state.

 Spoiler

Monster Manual + Sharp Plug + Wafer/Cancer + tons of red heart containers + some form healing (I've found Pyromaniac to be the most reliable, although you'll need tons of bombs on top of that) = easy mode Super Meat Boy and Bandage Girl unlocks.

Monster Manual has a relatively low chance of spawning a Meat Cube or Bandage Ball, so with this build you can essentially use the Monster Manual as much as you want in a single room. This is what I did to unlock the achievements because to hell with relying on RNG based boss spawns.

I don't know if this is worthy of spoilers but it may ruin the point of the achievement for some so I felt like doing it anyway.