Will encourage people to let enemies all the way into the hill instead of killing them as soon as they are spotted. This is the wrong way to play hill. You don't want people near your hill holder to keep them alive and prevent contested time which will stop your timer.

:Triple Threat: Halo 2: Anniversary MP: In Ricochet, pass once, score once, and kill at least one enemy in the same match.

Makes people force actions in an objective gametype that won't always make sense...

:Bombing Run: Halo 2: Anniversary MP: In Assault, take, plant, and score from the bomb spawn without dying or dropping the bomb.

This is going to make bomb holders hide in their own base and play SUPER conservatively in matches in an attempt to get this achievement. They'll hold onto the bomb instead of dropping it and killing someone at a distance when they have the chance to. While I love pulling off no death no drop runs, we don't need even MORE turtling in objective. Why not just "as a team, arm the bomb?"

:Cold Fusion: Halo 2: Anniversary MP: Kill an opponent by detonating a Fusion Coil.

Locks fusion coils into existing on all maps, even if a glitched one is found (ala Valhalla launch). Will make people not kill someone when it makes sense and just wait near coils to get someone.

:Counter-Sniped: Halo 2: Anniversary MP: With a Sniper Rifle or Beam Rifle kill an enemy that was zoomed in.

Luck based achievement. There's no way to tell someone is scoped in, it's not communicated to you in any way, yet they ask you to kill someone in a certain state. A bad idea that returns from 343's TU achievements from Reach.

:Eminent Domain: Halo 2: Anniversary MP: In Territories, control any 3 Territories simultaneously for 30 seconds.

Optimal play in Territories is to hold 2 of 3, to make the other team spawn predictably. If you go for all 3, it'll start a merry go round where the teams start rotating all the terrorities since they can spawn anywhere.

:Top Gungoose: Halo 2: Anniversary MP: Get a kill with the Gungoose while airborne.

So not only will people be driving around on geese for the entire match, they have to specifically be airborne while killing them.. this is like the Mowdown achievement in Halo 3 times ten in worseness.

:The Goose is Loose: Halo 2: Anniversary MP: Get 25 kills with the Gungoose in multiplayer.

See above.

:Shook the Hornet's Nest: Halo 2: Anniversary MP: Get 30 kills with the Hornet in multiplayer.

OH BOY CAN'T WAIT FOR ALL THE TEAMKILLING FOR THE HORNET. Also locks the hornet into the maps in matchmaking forever! Even if they are found to not work out!

:Skeet Shooter: Halo 2: Anniversary MP: Killed 15 opponents that were airborne from a Man Cannon.

Instead of killing enemies when spotted, people will wait for them to use a mancannon...

:Cold as Ice: Halo 2: Anniversary MP: On Lockdown, kill an opponent with the hanging ice

People will wait to kill people with the ice instead of just playing. Also locks the ice into existing on the map forever in some way, even though 343 has said they would delete it if it turns out to not work in MM. Good job.

:Power Play: Halo 2: Anniversary MP: On Warlord, get 5 center powerups that become available in a single game.

Camping around for the powerup instead of just playing. Influences how the map is played.

:Shields Up!: Halo 2: Anniversary MP: On Zenith, personally activate the center energy shield 3 times in one matchmade game.

So not only are you made to play Zenith a certain way, it's not even "your team", you have to do it yourself.. what.

:Wetwork: Halo 2: Anniversary MP: On Shrine in CTF, activate the enemy base waterfall and, before it stops, grab the flag.

So you are basically FORCED to give a tell to the other team on what you're about to do. Remember that activating the waterfall takes some firepower, so you basically have to go LOOK AT ME LOOK AT ME I'MMA GRABBING THE FLAG YO OTHER TEAM IMMA ON THE POLE POSITION HERP A DARP

:Grand Theft Halo: Halo 2: Anniversary MP: In one match, steal a total of 5 occupied vehicles from opponents.

People will try to board instead of destroying vehicles. And not just once, but five. times.

Imagine a team of 8 randoms that don't have the achievement yet.

Yep.

:Double Down: Halo 2: Anniversary MP: In Anniversary multiplayer, receive 2 or more Double Kill medals.

While this achievement will happen naturally for most people, it was a silly one in Halo 3, don't know why it's back.

:Warden: Halo 2: Anniversary MP: In Anniversary matchmaking, stop the killing spree of another player.

Straight up Call of Duty achievement.

:Blown Out of the Sky: Halo 2: Anniversary MP: Blow up the Banshee or Hornet in flight while piloted, with the Rocket Launcher.

Will cause people to save rockets for an air vehicle and not use it against incoming ground.

:Ninja Redux: Halo 2: Anniversary MP: Kill 5 people with melee from behind in Anniversary matchmaking.

Stop. Now people are just going to camp for this..

:Zealot: Halo 2: Anniversary MP: Win 10 multiplayer games as an Elite.

I play as Elite, love it. Don't make people play as Elites if they don't want to. They're easier to kill.