The Halo games have a billion achievements, particularly in the Master Chief Collection, and a lot of them are admittedly fun - but there are a bunch, where the idea of them alone makes me want to die.
The ones that I have 0 interest in even attempting are the LASO achievements, where LASO stands for "Legendary, All skulls on"
Legendary is the campaign's hardest difficulty, and skulls are modifiers which aim to make the game even harder. So things like not being able to see your weapon or ANY HUD elements, like reticle, ammo, health, or the one that limits health regeneration to ONLY when you punch an enemy, or my personal least favourite, the one where if you die, the whole level starts over.
Needing to complete an entire campaign like that? No way can I be bothered.