The Disposable sentry (which isn't a Mini-Sentry) is an upgrade avaiable for the Engineer in Mann Vs. Machine. The upgrade allows the Engineer to build an additional sentry gun which share similar stats with the Mini-sentry. The upgrade itself cost 500$, and cannot be upgraded further.

The Disposable sentry, like the Mini-sentry, cannot be upgraded nor repaired, but build 4 times faster than a normal Sentry and shoot faster than a Level 1 Sentry gun. It is also impossible to refill the Disposable Sentry's ammo.

After building his first sentry, the Engineer can build the Disposable Sentry and put it anywhere a normal Sentry can be built, but he cannot manually destroy it. When the Disposable Sentry runs out of ammo, it destroy itself and the Engineer can build an other one.

The Disposable sentry is almost a clone of the Mini-sentry, which means it also have his weaknesses : low health, low damages despite a wonderfull rate of fire, and lack of upgrading (I mean, you cannot upgrade it to level 3 and give it 2 gatling guns and a 4-rockets launcher). The Disposable Sentry cannot, like his brother, be repaired, but it's even more weaker than the Mini-Sentry if you add to this the fact you cannot refill ammo on the Disposable Sentry.

Plus, if a Giant of any kind step on the Disposable sentry, it will destroy it ; which means the Disposable sentry cannot be used for sentry-blocking (blocking robots with your sentry), and trying to do so will only encourage the destruction of the Disposable sentry.


The Disposable Sentry cost 130 metal to be built. This is as much as the standard Sentry Gun. 130 metal for an Engineer that can only carry 200 of it (exepted if upgraded) is a lot. Trying to build a Disposable Sentry in the middle of a robot push can easely makes the Engineer low on metal, preventing him from repairing his main Sentry gun.

You also cannot build the Disposable Sentry if you haven't built your main Snetry first ; which means the Disposable sentry cannot be used as a quick self-defense weapon.


The Disposable Sentry upgrade cost 500$, which is a lot (in early game at least). If you add to this all of the downsides above, it makes the price even less worth it if you compare if to other upgrades. This price also makes the Disposable sentry the most expensive upgrade point for the Engineer.


That's right : all those upgrades you put on Building Health and Sentry's rate of Fire does not affect the Disposable Sentry ! It makes it completly non-upgradable, no matter how much money you have, making the Disposable sentry less and less usefull as the waves goes on.

This is the main reason the Disposable sentry is hated that much by expert Mann Vs. Machine players. Since the only players that buy the upgrade, or at least most of them, attracted by "You only need 1 point in this upgrade to have it completly upgraded" feature, are beginners don't really knows how to play Engineer on Mann Vs. Machine, the Disposable Sentry is most of the time badly used (or at least, not as intended).


The number 2 mistake that makes the Disposable Sentry bad : a lot of players tend to put the Disposable sentries in positions where it gets rapidly destroyed, or even becomes useless. Most of the players place their sentry right under the robots spawn exit, where it becomes the first thing the robots see. An other kind of players, however, place their Disposable sentry right next to their main Sentry, where it cannot deal damages since the main Sentry kill most of the robots before they can get on the Disposable sentry's range.

Players think that, by placing the Disposable sentry behind the robots, it will not be noticed. Not only this is completly false but even if that was the case, it would make the Disposable sentry do some undesired side effects for the team, such as forcing Uber Medics to use their Ubercharge before some can kill them propely. It also force the robots to turn around to attack it, or to even change their movements, which is frustating for the Snipers and Spies of the team.


The number 1 reason the Disposable Sentry is absolutly not worth 500$ : after the Disposable Sentry is destroyed (by the robots or because it does not have any ammo left), Engineers being too focused on their main Sentry forgot about the Disposable Sentry, and the additionnal firepower the Disposable sentry gives to the team is left unused for the rest of the wave.

Too many players tend to forget that the Disposable Sentry get destroyed a lot, and that it needs to be rebuilt often. But between the army of robots attacking the Sentry and the harrasements of the Sentry Busters, the Engineer doesn't really have the time to care about the Disposable sentry.

So you are going to ask : "Why Valve added the Disposable sentry upgrade if this is that bad ?". The Disposable sentry is actually a good idea to have in certain situations, and it does make it usefull.

But whenever you use the Disposable sentry, remember to place it where it will not get shoot at ! This little gun isn't here to be a distraction, but an actual damage dealer. A good idea of placement is where the robots will attack your allies first, or even on high grounds (like, the bridge right next to the robot spawn on Decoy). And most importantly, re-build the Disposable sentry as much as you can, no matter where you put it, you have to rebuild it to make it worth.


This is the main situation you will use the Disposable sentry : around the end of the mission, you will have fully upgraded your Building Health, your Sentry rate of fire, have a point or two in Metal Capacity, and all the resistance upgrade you did not bought will not be usefull in the next wave, but despite that you still have some money left, and you want to be able to deal more damages. The Disposable Sentry in the best option here, since despite it does not deal a lot of damages it will deal damages and help you and your team.


You will not meet that situation where you need to cover more than one spot : most of the time you can place your sentry in a point where you will be sure all the robots will pass by. But in the rare case this happens, the Disposable Sentry might give you the additionnal fire source to defend from everywhere. It can also be usefull if you set it where Sniper bots comes, or to give you a hand when Spies attack you (because yes, Spies tend to ignore the Disposable Sentry and go for your main sentry first, then attack you)


FOR EXPERT MVM PLAYERS ONLY ! NEW PLAYERS SHOULD NOT TRY TO DO THIS DUE TO THE COMPLEXITY AND DANGER THIS TACTIC EXPOSE THE ENGINEER TO !

Now that I said that, you should know that playing a Gunslinger Engie is a BAD idea in Mvm, BUT it is more fun than staying behind your sentry the whole wave and only moving when a sentry Buster comes to just go back to your routine. Gunslinger Engie is a good alternative that will however force you to play like a Pyro, leaving your Sentry's upgrade behind. The Disposable Sentry can give you the additionnal firepower you might need to be usefull for your team and deal enough damages to the robots while upgrading your primary weapon. Just don't forget to build your sentries everytime they get destroyed.

I hope I gave answers to any new players readin this, and I hope expert Mann Vs. Machine players will not be mad because I said in the end that the Disposable Sentry can be good. I also hope people will give more love to this little fela and start to use it the way it supposed to be.

Don't forget to put a comment down here if you have anything to say, and don't forget to check my other guide :



https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=340356042
https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=390349912