...Should totally have been an achievement/trophy...

[Sniper Team 4]

The only thing I can think of off the top of my head is 'Catch!' for Black Ops:

Kill a zombie with a grenade. Not a grenade explosion, but by simply throwing it at them and hitting them. Like a baseball. I did it once with insta-kill on.

 

[Jailbird408]

Stupidly Brave - Defeat a Rare Nevi without retreating in Gravity Rush.
Why Won't You Die?! - Use five Special Attacks on the same Rare Nevi in Gravity Rush.
Gem Addict - Collect over 80000 precious gems in Gravity Rush.

 

[Bucky01]

TF2 - Who's the machine?: win a mann vs machine mission without losing a single wave.

dayz - i got your 4 basic food groups: have at least one of each item in your inventory at the same time: baked beans, cooked meat, a whiskey bottle and a tin can.
(beans, bacon, whiskey and lard )

dayz - nothing personal: kill someone who has recently bandaged and healed you.

dayz - don't leave me!: be killed by zombies after having your leg broken in a bear trap.

dayz - every little bit helps: kill and eat at least 10 rabbits.

dayz - like a moth to a flame: kill at least 5 zombies(or 2 humans) within 20 meters of a single campfire.

dayz - starved for help: loose at least 9000 blood from hunger then be healed by a blood bag.

dayz: you gotta shoot them in the head: kill at least 40 zombies with headshots in a single life.

that's all Ive got for the time being

EDIT #1: new ones for dayz are:

axe wielding murderer: kill 10 humans with just a hatchet in one life.

pandemic: catch the cold from someone who caught it from someone else.

zombie conga: have at least 30 zombies chasing you at a single time.

quick pitcher: kill a zombie with a can when you have aggro'd it.

hide and seek champion: kill 10 people in a single life while using a thermal scoped weapon.

jackpot: successfully duped a coyote backpack when equipping a gillie suit/camo vest.

be prepared: fill a tent you own to its maximum.

target at 50 meters: while using range finders watch someone be killed by a sniper rifle.

scout master: obtain all possible tools for your tool belt in a single life.

shinobi: have at least 50 zombies lose aggro on you in a single life.

bar fight: hit a zombie/player with a whiskey bottle in elektro's bar.

long distance runner: run at least 10km after spawning before picking up a single primary/secondary weapon.

its a trap!: kill at least 3 players with a single satchel charge detonation.

nectar of the gods: have at least 3 cans of mountain dew in your main inventory at the same time.

isn't it contaminated?: fill up a water bottle from a water source with a dead zombie/player in it.

what's mine is mine, and what's yours is mine: loot 20 player corpses from people you have killed.

silence is golden: kill "x" amount of players/zombies using only silenced weapons and silenced ammo.

nav man: be the passenger on a vehicle that's traveled at least 15km while possessing a GPS.

this is my rifle, this is my gun.: kill at least 50 players/zombies with a single weapon in a life.

 

[CannibalCorpses]

Skyrim: 'Unheard of round here': complete the game without falling foul of any bugs
GTA4: 'Assisted suicide': Push someone into the path of an oncoming tram
CoD: 'Flash, bang, wallop': Kill someone with a flashbang in multiplayer
Dead Rising: 'They graped me': Get captured by a bunch of cultists and taken to their lair
Alpha Protocol: '2 heads are better than 1': Have a double encounter while strapped to the table
The Darkness: 'Epic': You want it all but you can't have it (check the voice actor)

 

[Fijiman]

Gears of War 3:
Like A Boss: defeat all of the bosses in a a single Hoard match without dieing.
Can't Stop Me Now: Complete a Hoard match without failing a single wave.

I'm sure I could think of more, but that's all I got for now.

 

[Nekron_X]

Prototype 2: Lucky F*****: while driving a tank during a story mission, get flung by a hydra onto the top of a building and have the tank survive(happened to me on my 1st playthrough)

Fate unlimited codes(doesn't actually have achievements/trophies but...): I am the bone of my sword: use archers unlimited blade works in an actual match.


That's all i've got for now.

 

[KoudelkaMorgan]

Borderlands - "I C what you did thar" aka "The D list" aka "Rated E for Everyone"
Zooming in on Moxxi's bewbs with any weapon.

Metroid Fusion - "All I need is one" Beating the game with 1% items attained.
Seriously that was a pain in the ass to do. Especially killing the Nightmare.

 

[White_Lama]

World of Warcraft: "Fishcrit" - Slap a raid boss in the face with either "Old Crafty" or "Old Ironjaw". I had to add this because I usually do that myself (to great joy of my raid team) and I would love if that would be an achievement or a title in-game

Skyrim: 'Unheard of round here': complete the game without falling foul of any bugs.

I would be able to sell this achievement to people then since I have played it since the night of the release and haven't seen any bugs yet

 

[Alakaizer]

Dark Souls-Completely Kill-crazy: murder every single NPC, without talking to any of them.

 

[luckshotpro]

Skyrim: What game is this? - Install 10 mods
Repetition: Smith 1000 Iron Daggers
Domestic Violence: Punch your spouse while wearing a ring
Any day now...: Reach level 25 without visiting the Greybeards
Traitor: Cure your Vampirism and become a Werewolf,or vice versa

 

[D-Class 198482]

Fallout New Vegas - The Walking Head: Decapitate 1000 Feral Ghouls
Dead Island - Like A Chef: Set a zombie on fire and cut them to pieces.
Dead Island - A Flaming Pile Of Bull: Kill a Ram using only enviornmental fire damage
Team Fortress 2 - Nope: Go through an entire round as an Engineer without your buildings being damaged
Portal 2 - Look It Up On Gamefaqs: Spend 2 hours on a single puzzle
Garrys Mod - Unimpressed: Spawn 20 Scripted NPCs
Counter Strike: Source - Look Out Below: Kill 20 enemies with attacks from above
I'll probably add more later
Also, hooray for JonTron references: I dare you to find it.

 

[CannibalCorpses]

Skyrim: 'Unheard of round here': complete the game without falling foul of any bugs.

I would be able to sell this achievement to people then since I have played it since the night of the release and haven't seen any bugs yet

Thats amazing because i managed to break a quest on every plot line. The companion quest where the dude turns into a wolf, he wouldn't change. The thieves guild had the woman that wouldn't stop doing laps and activate the next scene. In the mages guild i had a teacher that wouldnt cast spells at me but expected me to reflect them. The brotherhood had the coffin scene but without any sounds to explain what was going on (i went for a coffee break the second time it 'crashed' and it loaded past the silent black screen). Those are just some of the specific crashes and then there was all the random lockups or just bizarre glitches.

All in 75 hours of gameplay

 

[jbm1986]

Bioshock 2
Puppet Master - Kill a splicer with the head of Andrew Ryan's animatronic puppet.

^Maybe this?

Gears of War 3:

[Hindenburg 2.0] - Kill 100 gas barges. It's also a reference to Archer.

 

[King Billi]

Dark Souls

'Were you prepared?' Die for the first time.

 

[ItsAChiaotzu]

Dark Souls

Chosen Undead: Complete the game without levelling.

 

[Grouchy Imp_v1legacy]

CoD: 'Flash, bang, wallop': Kill someone with a flashbang in multiplayer

The games already kinda have this. Ok, they're in-game challenges rather than 360 achievements, but 'Think Fast', 'Think Fast: Stun' and 'Think Fast: Flash' are multiplayer challenges that relate to killing enemies with direct impacts from grenades of the indicated type, and 'Ouch' is the same challenge but for the under-barrel GL. They get unlocked around the mid-forties level mark if I remember correctly.

OT:

'Get a job!' : Reach level 30 in Skyrim without joining any factions.

'With friends like you...' : Recruit every follower in Fallout: New Vegas - and have them die in your service.

'That's why they're called your problems.' : Complete Deus Ex: Human Revolution without performing any side quests.

That's all I can think of at the moment.

 

[Vegosiux]

Assassins Creed:

Shh... I'm an Assassin - Kill a target and wait in plain sight until the body is discovered.

Going "Nin nin nin!" about it is optional?

Hmm all I got is this:

Big Badass Lone Wolf - complete a Persona game without social links, and entirely solo.

 

[w9496]

The Darkness: 'Epic': You want it all but you can't have it (check the voice actor)

That reference. I get it.

OT:
I've been here...: find 20 locations in Skyrim.
I've been there...: find 100 locations in Skyrim.
I've been everywhere!: find every location in Skyrim.

Needs more ketchup: chainsaw 5 enemies in a row in Gears of War 3.
Put you out of my misery: killed a nemesis in Gears of War 3.
It works great, trust me: trade a weapon that only has one bullet in Gears of War 3.

Wait, what?: pounce a survivor after leaping off of three walls in Left 4 Dead 2.