Have a dispenser heal 3 teammates at the same time.
Provide an enemy player with a freeze cam of you and the sentry that just killed them.
Have your sentry kill the enemy that just killed you within 10 seconds.
Help a teammate construct a building.
Engineer Milestone 1
Achieve 5 of the achievements in the Engineer pack.
Get 10 assists with another Engineer where a sentry gun was involved in the kill.
Use your shotgun to finish off an enemy recently damaged by your sentry gun.
If You Build It, They Will Die
Haul a level 3 sentry gun into a position where it achieves a kill shortly after being redeployed.
Doc, Stock, and Barrel
Repair a sentry gun under fire while being healed by a Medic.
The Wrench Connection
Kill a disguised spy with your Wrench.
Engineer Milestone 2
Achieve 11 of the achievements in the Engineer pack.
Use a revenge crit to kill the enemy player that destroyed your sentry gun.
Kill a spy and two sappers within 10 seconds.
Manage to get to and then remove a sapper placed on your building while you were several meters away.
Engineer Milestone 3
Achieve 17 of the achievements in the Engineer pack.
Haul buildings 1 km over your career.
Teleport 100 team members into battle.
Built to Last
Help a single building tank over 2000 damage without being destroyed.
Kill 3 enemies with revenge crits without dying.
The Extinguished Gentleman
Have dispensers you built extinguish 20 burning players.
Upgrade 50 buildings built by other team members.
No Man's Land
Use a sentry gun to kill 25 enemy players that are capturing a point.
Honky Tonk Man
Smash an enemy player's head in with your guitar.
Pownd on the Range
Kill 10 enemies outside the normal sentry gun range using the Wrangler.
Fistful of Sappers
Destroy 25 sappers on buildings built by other team members.
Pick up 10,000 waste metal from pieces of destroyed buildings.
Provide an enemy player with a freeze cam of your guitar playing skills.
Perform 50 repairs and/or reloads on a Sentry gun being Wrangled by another Engineer.
(Not So) Lonely Are the Brave
Keep a Heavy healed with your dispenser while he gains 5 kills.
Have a sentry shielded by the Wrangler absorb 500 damage without being destroyed.
Destroy an enemy Engineer's sentry gun with a sentry under control of your Wrangler.
Have dispensers you created dispense a combined amount of 100,000 health over your career.
Kill 20 players carrying the intelligence.
Kill 3 cloaked Spies with a sentry gun under control of your Wrangler.
Kill 10 Snipers with a sentry gun under control of your Wrangler.
How the Pests Was Gunned
Destroy 50 enemy stickybombs lying in range of friendly buildings.
Best Little Slaughterhouse in Texas
Rack up 5000 kills with your sentry guns.
Circle the Wagons
Repair 50,000 damage to friendly buildings constructed by other players.