Left 4 Dead 2 achievements

As the Jockey, ride the Survivors twice in a single life.

Survive the Parish campaign.

Survive the Swamp Fever campaign.

As the Jockey, ride a Survivor for more than 12 seconds.

Use every melee weapon to kill Common Infected.

Survive the Hard Rain campaign.

As the Spitter, hit every Survivor with a single acid patch.

Ignite 50 Common Infected with incendiary ammo.

Decapitate 200 Infected with a melee weapon.

Survive the Dark Carnival campaign.

Survive The Passing Campaign.

Kill 100 Common Infected with the chainsaw.