Buff 15 teammates with the Buff Banner in a single life.
This achievement is either very easy or very hard, depending on your ability to stay alive and the size of your team. You first need the Buff Banner, which can be acquired through a random drop or through the Soldier milestones. You then need to play on a server with a bunch of people. Playing on a full 32-player server is the best, as you will have exactly 15 other players to give the buff to. Simply get the buff and run around to buff all of your teammates, and you will get the achievement.
Farming this can be tedious or easy, depending on the amount of players that are helping or hindering you. The key here is that it has to be in a single life, not a single activation. This means that you can get the Buff Banner charged, use it until it runs out, charge it up again, and use it again. If you charge 8 people twice, you will get the achievement as if you had charged 15 people at once. It's as simple as that. Presumably, if you had only three people (yourself and two others) you could do the buff 15 times, but that is exceedingly tedious.
Note: The achievement title is once again another pop culture reference. In this case, it's the Beastie Boys, a rap group that performed hits such as Sabotage, Intergalatic, and FIght For Your Right (To Party).
Out, Damned Scot!
Kill 500 enemy Demomen
Another achievement that is simply a grind, this one has you killing 500 Demomen. It's an obvious reference to the WAR update, where the Soldier and Demoman fought over who would receive the Gunboats. Simply kill Demomen as you play the Soldier class. It's as simple as that. You have a slight advantage thanks to your longer range and greater health, so use it. Just watch out for thos stickies.
Note: The achievement title is a reference to the line "Out, damned spot!" from Shakespeare's play Macbeth. This line was spoken by lady Macbeth as she contemplates her manipulative crime. The spot is Duncan's blood, and while it is not actually on her hands, she sees it there as a manifestation of her guilt. The Demoman has an achievement that also reference this play titled Laddy Mcdeth.
Frags of our Fathers
Gib 1000 people.
Hey! It's another grind achievement! We just love these achievements, mainly because they almost force players to play the normal game as opposed to farming achievements. In order to gib players, you must kill them with your rocket launcher. The closer they are to the blast center when they die, the more chance they have of being gibbed. It's as simple as that. We highly recommend that you do not farm this, as it will take a very, very long time. Just play the game normally. If you feel the need to farm, choose another achievement.
Note: The achievement title is a reference to the book (and subsequent film adaptation) Flags of our Fathers. It is about the invasion of Iwo Jima by American forces during World War 2.
Kill a Pyro who has airblasted one of your rockets in the last 10 seconds.
This is one of the most difficult achievements for the Soldier. Not because it's especially hard to kill a Pyro with a rocket, but that it's hard to kill one who is good at reflecting rockets. You will have to catch the Pyro off-guard in an open area to get this achievement. Once you do so, just shoot him with your shotgun. As he gets close, start blasting away with rockets. He'll likely reflect a few, but if you are lucky, he'll miss one, take a hit, and gib, getting you the achievement.
To farm this, simply get a friend as Pyro who is willing to die. Have him sit somewhere as you whittle away his health. Then shoot two rockets at him. When he reflects the first, he should take the second, which will kill him. This is a funny achievement to farm alongside the Pyro achievement for killing a Soldier with his own crit rocket, as he can reflect the first (a crit) and die to the second, thus killing you both and getting you both an achievement.
Note: Another pop culture reference. This one is to the concept of draft dodging, where citizens avoid being drafted into their nation's army. This was especially prevalent during the Vietnam War.
Ain't Got Time to Bleed
Kill 3 players with the Equalizer in a single life without being healed.
This achievement can be tough or easy, depending on the awareness of the players you are fighting. To prep yourself for it, it is suggested that you damage yourself twice with your own Rocket Launcher. This will put you at 25 health, making you move significantly faster (almost like a Scout) and kill enemies in one to two hits. Simply run around and kill them with the Equalizer. It's as simple as that. If you are healed by any means, such as through a medikit or Medic, you will have to start the achievement over.
To farm this achievement, get a friend to play as the Scout. Damage yourself twice with the Rocket Launcher, then hit him with the Equalizer. Once he respawns, do it again. Repeat until you get the achievement. One of the easiest achievements to farm, assuming you have the Equalizer.
Note: The reference here is to the line "Ain't Got Time To Bleed" from the hit action movie The Predator.