OK, on to the real stuff…The dispenser. Yes, I said the dispenser, it’s a powerful weapon when used properly! A fully stocked dispenser makes a pipebomb look like a firecracker. Yes, it can resupply your team, but that’s generally not it’s real use. It’s real main use is to BLOW OBLIVIOUS PLAYERS INTO BLOODY CHUNKS! *ahem* You may only have one dispenser constructed at a time. It takes 100 metal units to build a dispenser and takes 3 seconds. If you’re under attack and you need to abort the building process, just press your special key and MOVE QUICKLY! =) Over time the dispenser will slowly create ammo and armor by itself, but stocking it is much faster: You can stock up to 300 rockets in a dispenser, which gets truly messy when an enemy happens to be standing next to it. (just be careful when friendly fire is on!) To stock it you just hit it with the wrench and press 1. To maximize the number of rockets per trip I usually load it twice, discard twice, then pick up the packs and load again to provide it with 17 extra rockets. (For the longest time I couldn’t figure out how to do this because I was actually hitting air. You have to aim waaay down or duck to actually hit it. :) It also provides an “enemies are using your dispenser!” warning when used by the enemy team, even if a disguised spy is touching it, which is a helpful penetration warning a good engy will never underestimate.

Ideally you will want to set it up where it blocks off an entry, but it won’t let you set it up unless there is enough space to barely squeeze through on one side. Theoretically, at least; I’ve managed to set them up in 2fort in the elevator shaft room entryway, where there was no possible way into the room with the dispenser intact without jump ducking onto it and crawling over, which is WAY more time than I need to blow it. =) This is another function of the dispenser. It at least slows an enemy down, and in some cases halts them completely for a moment while they stand back to destroy it. Since a sentry takes a second to lock onto an enemy, sometimes a scout is able to dash past your gun and take little or no damage, but if you set up the dispenser in their path they’re not likely to make it. In this regard location is vital; ideally you want to set it up in a very narrow area the enemy must get through to get to the goal, but not one in which they have a long distance over which to shoot it: you want it to be a surprise and detonate it right in the face, which makes small rooms or short narrow hallways ideal. For example, the warden’s office in rock2 right next to the key, or the flag room entry or tops of elevator lifts in the attic of the well; surprising places that alert you when enemies are incoming and gives you a good chance to liquefy them! You can also use it to cover your sentry’s blind spot, just place it in a spot you know an enemy will try to kill your sentry from and let them have it! One other application I should mention while I’m writing this is that you can dispenser jump if you build, load the appropriate number of rockets or wait for it to build them up, and then jump while simultaneously blowing the dispenser. I’ve never found it terribly useful, but you can pull off some neat tricks with it, like setting it up so that it can launch you up into the roof area in No Mans Land (if timed properly), allowing you to set up a sentry there. Just so ya know. =)

-= Sentry =-

- Placement -

OK, onto the sentry…This is where things get complicated. Again, location is EVERYTHING. You want a spot that has good strategic value and is easily defensible. Bear in mind there are no perfect spots, and you WILL lose your sentry sooner or later, so get over it. =) You want it in an area close to respawn if it’s reasonable so that you can defend it quickly, and guarding the path to the enemy’s goal, obviously. Ideally it should be impossible to bypass the sentry, which often means you will have to set up very close to the flag. Try to set it up with a height advantage if possible, as that makes it harder to destroy with grenades and is often less noticeable. Also look for areas where it will be less noticeable, such as dark corners. To get it pointing in the correct direction you may need to rotate your gun, but if you initially set it up so that it’s facing the desired direction (180 behind you when building) you probably won’t have to, just be wary of standing in the line of fire while upgrading. If you want to set it up overlooking an edge try to build it with the edge on your right, that way you will only have to rotate it 1-3 times instead of 5-7. Obviously, you may only have one sentry gun constructed at a time: You can't build a second one as long as the first one still exists. It takes 130 metal units to build/upgrade a sentry and 5 seconds of vulnerability. Again, since you can’t fire or prime a grenade while building, you can and should abort if an enemy catches you while you’re building, and you get to keep your metal for another try should you survive.

You can also build on pretty much on any flat surface, and some that really aren’t so flat, as long as there’s enough room, including underwater. Try http://tfc.pcgame.com for some downloadable demos on some off-the-wall places for sentry placement. Most maps have some sort of water entrance. If you’re lucky, you can set it up so that just as an intruder is about to drown, they have to deal with a little chaingun fire as well as the need for oxygen. Now, I will caution you, these places are usually not anywhere near resupply areas, so upgrading your water defense sentry can take a little while. And make sure you come up for air just before you start to build, or else you might drown, maybe even before you can complete the sentry! Also, a lot of maps have crates you can put your gun on top of, but that doesn't necessarily mean you have to get back on top of the crate for maintenance. Jump, hit the gun with your wrench, and when you get back down, hopefully the menu will stay open. Sometimes, especially if the gun isn't very close to the edge, it won't, but it's a worthwhile trick to save time. The less time you're trying to improve your gun, the more time you're able to do other things, and the less likely you are to get gibbed while trying to reload your sentry. Other odd but effective places include such places as the battlement rails or the spotlight towers of rock2, or the attic of the Well. To build on the rails, jump up on them and build facing parallel to the rails. To build on the tower, build so that you’re on one side of the spire and the gun’s on the other. Even once you master this technique it will sometimes malfunction and explode once you complete building. To build in the attic, make sure that one leg of the tripod is hanging into open space so that it can shoot straight down. Look for odd places to put sentries that are an advantage over simple flat floors.

Believe it or not, a few “feet” one way or another can also make a world of difference when sentrybuilding. Often a sentry just barely hanging over the edge of a ramp or ledge can cover what would otherwise be its vulnerable blind spot. The attic of the Well is a good example of this: You want to set it up so that one leg of the tripod is hanging out into space so that it can fire straight down. If possible, try to set it up in a long narrow hallway where they have to get past it to get to a goal, or in an open area where they can’t shoot it from outside it’s tracking range. Sentries work best in the early stages of a fight to ward off scouts, spies and medics. As the battle heats up, if you can spare it, get a heavier class like a HWG or soldier to stand guard with you, because you WILL need it. For example, I can usually stop one or sometimes even two attackers at a time, but when they come in a steady stream and I die or I have to go resupply, I’d like to have somebody else who can hold down the fort while I’m gone.

Once the fight has heated up, tell your (other) teammates to stay out of the flag room or the area the sentry’s set up in if it’s out of the way of normal traffic. It's somewhat difficult to discover spies if your own teammates come running in all the time. Tell them if they come in towards the flag room or sentry area without warning, they will be shot, and do it!

The trick to keeping your sentry alive for the long haul is to make sure that it can’t be grenaded or shot at from outside its RLOS (Range/Line Of Sight) distance, which is much harder than it sounds. Corners are a blessing at first, because enemies will come running straight into a line of fire they can’t escape in time; but a curse later, since the sentry takes a moment to lock on and won’t target partially hidden enemies. A smart enemy will pop into sight and drop a grenade then hide behind the corner while the sentry gets blasted, or just barely peek around a corner and shoot it with a nailgun. Ideally you’d like to place it where the sentry’s RLOS ends just at the far wall of a corner, and can’t use that corner for cover, so that enemies have to face it but can’t throw a grenade at it effectively. Unfortunately, I’ve never seen an ideal situation, so be prepared to defend your sentry a large amount of the time. Spies are a prime example of this; I’ll talk later on them in particular.

- The Sentry Maintenance Menu -

To build a sentry or dispenser, you must use the special key and select the appropriate option from the menu, making sure you have enough metal to build that item. If you do not, the option will not be given to you. To upgrade any friendly sentry (not just yours), whack it with the wrench and choose option 2 from the menu, making sure that you have the necessary 130 units of metal. There are 3 levels, each better than the last in terms of accuracy, firepower, ROF, amount of ammo stored, and health. To reload a sentry select option 1 to load it using your reserve ammo. When loading, the first press will load all but 10 of the shells not already in your gun; The second will load those last 10. Rockets cannot be loaded into anything but a Level 3 sentry. Option 3 allows you to repair the sentry if it’s damaged, and option 4 dismantles it (giving you back ½ of the metal used to build it, or 65 units) which allows you to reposition it or undo the work of a llama teammate blocking your respawn. Definitely don’t ever BE that llama teammate, and generally if it’s not yours you should ask the engineer to move his gun rather than dismantle it yourself. Option 6 will rotate the sentry gun 45 degrees to the left (counterclockwise) which allows it to spot and kill enemies more quickly and efficiently when pointed in the right direction.

- Range -

Range is an important issue regarding sentries. All non-grenade, non-melee weapons have a longer range than the sentry’s RLOS, which means you have to be careful not to place your sentry in open sight or it will quickly be destroyed. Also try to make sure that enemies can’t sneak up behind it if possible. It does actually have a detection range for the rear and flanks, but it’s very limited; any class can take out a sentry from behind with no difficulty if they can stay out of that short detection range. Much of the time your opponents won’t be trying to kill it with guns, however; they often come rushing in trying to grenade it to death, which unfortunately all too easy. Normal handgrenades do about 60% damage to a level 3 sentry if properly placed. MIRVs are instant death, don’t even bother trying to save your sentry. Nailgrenades depend on how close it lands to your sentry, as each nail does 10% damage and you still have to worry about the blast, which is equivalent to a standard hand-grenade. Napalm grenades will kill your sentry unless you are willing to stand in the flames and repair it, which I usually recommend under most circumstances, but use your judgment. Hallucination grenades, concussion grenades, and caltrops do no damage to sentries, obviously. All in all, grenades are a sentry’s worst nightmare. So, it comes as no surprise that height confers a large advantage to a sentry’s survival rate. An opponent has to decrease the distance from the sentry to achieve the height needed to arc the grenade into it, which often of course puts them into the RLOS of the sentry and nets you a frag. Be especially wary of spies, however, because any experienced player will realize this and either send in another player as a spy to kill your sentry or switch himself or herself to take it out. As I said, I’ll talk specifically about spies later, whole tactics sometimes revolve around stopping them.

- Warning System -

Like the dispenser, another valuable asset the sentry provides is a warning system, often better than the dispenser, although sometimes at a certain cost. If you’re observant, even when you’re well out of hearing range you’ll notice your gun is firing due to the decreasing ammo counter. If you also see a kill register, you get an added bonus, but if you’re not otherwise engaged at the moment I suggest you run down anyway to make sure that the “fragee” was working solo and doesn’t have a buddy plotting the untimely demise of your sentry. Plus, while you’re down there, you might as well restock your gun, because I’ve found that enemies tend to come running in just as you leave to resupply and you want to be there to greet them with a full sentry and a primed EMP just in case. If your sentry is taking damage but isn’t firing, that means one of two things; either there’s a spy in the house or a clever enemy has found a convenient corner from which to shoot at your sentry. Often you can even identify the class attacking your sentry by the rate and continuity of health loss; if it’s a steady drop in health, you can bet it’s a scout, medic or possibly a sniper using a nailgun. If you play way too much (like me), you can tell a medic by the RATE of drop in health, as it’s slightly faster. If it’s in 2 big packets of damage, you probably have a spy, but not necessarily, as it may be another class has found a good spot to angle in a couple of grenades. Demos, HWGs, and enemy engineers are dead giveaways, because they usually use MIRVs or EMPs, which can kill sentries instantly. (although depending on the distance from the sentry, a MIRV can look like 2 handgrenades) Sometimes a sniper will get a good around-the-corner shot and just kill it with a single charged shot. Pyros use napalm grenades, which just bleed off health in small packets, and soldiers tend to strafe around a corner, squeeze off a rocket, dart back in before the sentry fires, and repeat. This takes 3 rockets if they’re dead on, so if you do happen to be there defending at the moment, repair it after the second rocket as they only have 4 to launch at a time. (Can you tell I’ve played just a bit too much TFC as an engineer? =) Repairing a sentry takes a small amount of metal, and the repair cost is free if you upgrade the gun, so there’s no need to separately repair and upgrade a Level 2 gun for example.

In any case, since you’re probably out at the moment and won’t be there to repair, get there immediately, you’re already too late to save your sentry, but you will still need to eliminate that threat as soon as possible. You do have a slight advantage in that the player will know you are coming, but often won’t know when or from what direction, and will be racing towards the goal as quickly as possible. I’ve often used this to my advantage by placing a fully loaded dispenser in the warden’s office of rock2 and detonating it just as they enter the room, because they are most vulnerable at that moment. They know you are coming, possibly with backup, and need to grab that key/flag/whatever as quickly as possible and run! They never bother to check for traps until it’s too late, unless of course, you’ve hit them with that lil trick before. Even then sometimes they forget, especially if it’s been a small while since they got hit with that one. =)

- Rebuilding -

Which leads me right into rebuilding… If your sentry gets demolished near the key/flag/whatever and you can't immediately kill the fleeing attacker, don't bother chasing them down. Stay back and rebuild as soon as they get away. Word will probably get out that the sentry is down, and you'll be flooded with scouts and medics or other fast classes before you know it. If you chase them halfway across the map only to get killed, not only will they still cap the flag or whatever, but also by the time you respawn you will be swarmed with enemies and won’t be able to keep a sentry up for long, ensuring extra caps for the opposing team. Go for the long term defense rather than the short term.

After you’ve (hopefully) killed the enemy messily and have made sure the rest of the defense has solidified to give you time, you need to get your sentry and dispenser back up as soon as possible. Run into respawn, grab what you can, including grenades if possible, and run right to the spot you’ve selected to build your sentry. Vary your sentry locations each time you rebuild! If you build in the same location each time, your opponents will just lob in grenades to kill it each time without even bothering to check to see if it’s there, and all that work will be wasted. If you move it around, they may only damage it or miss completely, and thinking it’s safe, run straight into the RLOS and earn you another frag. Scout out each map and find AT LEAST 6 good spots for a sentry; trust me on this one, you will NEVER find a map with less than 6 spots, and often there’s at least one or two dozen in your base area alone! If you have other engys on your team you will often have to go with an alternate, which is often actually desirable as it strengthens your defense and gives you experience with a new site instead of the same old spot you always pick. If you’re solo, by moving it you keep them guessing, and will make their lives just a little harder. Keep in mind you will need adequate defense to rebuild, so if enemies keep streaming in, grit your teeth and wade into the fray, because you’re a sitting duck while building. Remember that it’s possible to abort building by pressing the special key a second time with no metal loss, but don’t count on that to keep you from dying, you’ll still have to move out of the way VERY quickly. To build you must have sufficient defensive cover or you and your newly constructed sentry won’t stand a chance. Also keep in mind proximity to resupply points on the map if you are under heavy pressure, as enemies can easily kill a weak sentry while you are away getting ammo and metal. All too often I’ve been away to get metal and ammo for a Level 2 sentry and had it destroyed while I was out. If possible, you may need a teammate to ferry metal for you, although this isn’t ideal since you will still need to load it with ammo, but at least you can get it up to level 3 this way fairly quickly.

- Defending -

Regarding defending your sentry: You should never be too far away it to respond quickly should the need arise, unless you are specifically on offense or lagging. By the way, engineers are the best class to play when you’re lagging, because as a fellow engy once said, “Thy S-gun knows not of ping.” Whatever the reason, sometimes you just won’t be able to save it in time, but you will still need to kill the attacker. Hopefully, though, you will be able to stop the attacker in time, and repair any damage done. This is important because more enemies will be coming in soon and will also be trying to destroy your sentry, so you can’t have a weakened one to present as an inviting target.

Treat every sentry gun on your team as your gun, or your team will have a much weaker defense. Don’t allow anyone to attack any of your team’s guns if at all possible, and make sure they are repaired, stocked, and upgraded at all times, don’t just let them sit there damaged or they will be quickly destroyed and you will be overrun. Especially important in this respect are spies. You are your sentry’s only hope against spies, so learn to identify them well by their behavior and giveaways.

- Floating Sentries -

It is possible to build a sentry so that it “floats” in midair. The trick to this is to have something temporary to build on, like a dispenser or a willing teammate. You will need to be on the same level as the height of the sentry you wish to build, so this limits your locations to ledges, crates, or something similar unless you have more than one dispenser or teammate available. Get on top of the crate/ledge/whatever and attempt to build on your dispenser or teammate’s head. Getting it so that the relative heights are equal is difficult and the spot in which it will allow you to build is incredibly small, so don’t expect instant success even once you’ve succeeded a few times! When it’s completed you can blow the dispenser or have the teammate move and the tripod part of the sentry will drop but the body of the sentry will hang in the air. Keep in mind you may need to keep the dispenser or teammate there if you want to upgrade and load your sentry, as it may be unreachable in some situations. The big downside to floating sentries is that they take FAR longer to set up than a normal sentry, so you will need a solid defense if you hope to build one, as you’re even more vulnerable than normal. I’ve also found that floating sentries are only slightly harder to kill, and so in my opinion aren’t work the large amounts of extra time and resources necessary. I would say the only time it’s worthwhile is when you set it up on the “back side” of a crate so that it’s harder to grenade, or when you can set it up to shoot under a ledge that would otherwise be its blind spot, which is quite tough to pull off. All in all, I’d say it’s a nice trick to know but not at all useful in reality. However, if you can somehow pull it off quickly and effectively, go ahead and use it.