By killing a combo class such as Medic, Heavy or Demoman, Sniper can start a push for his team or stop an enemy push in its tracks by reducing a team's offensive or defensive capabilities. This is Sniper's main responsibility, and most of his other goals are directly tied to this objective.
In higher levels of play, many teams' play-styles tend to revolve around Sniper, with Medic overhealing him and Engineer setting up a Sentry Gun to protect him from enemies. Sniper is greatly valued in Highlander, and with good reason; many Highlander maps have long sightlines that make him near-impossible to fight against; sometimes, the only way to kill him is with another Sniper.
- Nearby enemies. Depending on the map, your life may be more or less valuable than Demoman or Medic. However, you are still a vital asset to a teamfight, so defend yourself from attacking enemies before going for picks.
- The other Sniper. The enemy Sniper poses the greatest threat to your life; often, he will be the only enemy who can even attempt to kill you. Thus, you will be locked in a duel with him until one of you is dead. Even if he isn't shooting at you, he can kill your team from a distance. Shoot him as soon as possible; if he's nowhere in sight, ask your team to locate him - he may be attempting to flank you.
- The Medic. A good Medic will rarely step into your sightline, but if he overextends, killing him is relatively easy - an uncharged headshot or a fully charged bodyshot will send him back to respawn, giving your team about a minute until an enemy Ubercharge is ready. Without healing, the enemy will usually be forced to retreat, allowing your team's flank to land an easy pick.
- The Demoman. Demoman's area denial is a formidable defense against your team; he can easily block your flank routes and choke points with Stickybombs, and his grenades can deal 400 damage in a few seconds. Taking him out destroys his stickies and prevents him from spamming explosives, allowing your team to move in.
- The Heavy. Heavy's job is to block attack intended for his teammates and grind down overextending enemies. He will almost always have overheal from the enemy Medic, making him very difficult for the rest of your team to fight. Despite his large hitbox and slow movement speed, a good Heavy will duck and weave out of your shots, causing you to waste time charging shots to try to hit him. However, when he is killed the enemy team becomes more vulnerable to spam and flanks, and the enemy Demoman will lose his main defense.
- The Engineer. Without his buildings, Engineer doesn't pose much of a threat to you or your team. However, his nest makes a stellar defense, as long as he's maintaining it. Once he dies, his buildings are much easier to demolish - if you have a sightline, shoot them. If Engineer is running the Gunslinger, picking him off isn't as high a priority, as Mini-Sentries have fairly little area-denial capability.
- The Pyro. Pyro has very limited range (even with the flare gun and other projectile weapons), but makes for a effective bodyguard for the enemy combo; they can airblast projectiles, harass with afterburn and ignite approaching flank classes. While they don't pose a massive threat to your team, they can deny projectile-based classes from pushing in. Killing them gives your team's Spy as a lot more breathing room, and your Soldier and Demo are free to spam explosives without the threat of them being reflected.
- The Soldier. In most Highlander matches, Soldier will suicide-bomb valuable classes like you in order to open up room for his team to move in. While rocket jumping, he is difficult to hit, but on the ground, he is easily headshot thanks to his slow movement speed. Unfortunately, when attacking you, he will often rocket jump - practicing airshots is the only way to counter this strategy.
- The Spy. Spy is deadly to you as you are to him. Thanks to his on-demand Invisibility Cloak, you will rarely get the chance to pick him before he attacks you. Always listen for the sound of his decloaks, and alert your team to his presence - Spy is weak in direct combat and is quickly killed once he loses the element of surprise. If no fighting is going on, you occasionally may hear his footsteps. Keep your distance from Spy and try to avoid engaging him; unless you can headshot him at close range, he can gun you down with his Revolver.
- The Scout. Scout is rarely a threat to you unless he manages to flank your team and attack you head on. Killing him won't turn the tide of a game, but his double capture rate speeds up capturing time in Stopwatch Mode so denying him the objective is helpful.
As Sniper, you are strongest when you have access to long sightlines that allow you to see the enemy team. Often, these sightlines can be used the enemy Sniper, which typically leads to Sniper duels. The Sniper that wins gains a significant advantage - he can pick important enemy players without fear of being headshot. If you can kill the enemy Sniper, do so. If he is too protected by his team, consider utilizing a different sightline, or try to flank him - shoot him from an unexpected position and then retreat.
While Sniper battles boil down to shooting the other Sniper before he can shoot you, there is a great deal of nuance to this particular interaction. Many servers are dedicated to letting Snipers fight each other at long range to refine their aim and techniques. Some Snipers prefer to strafe around quickly left and right while out of scope and wait for the other Sniper to scope in (slowing his movement speed to a crawl) before taking a shot. Other Snipers decide to disregard the "second scoping" tactic and shoot first every time. Both techniques have their benefits and drawbacks; second-scoping allows for an easier kill should the enemy miss, but risks being killed if the enemy has excellent aim.
Sniper can shut down entire attack routes with his ability to kill every class in the game in one shot, given proper preparations and steady aim. Even his mere presence can cause enemies to back off - Spy may opt to use a friendly disguise to keep the enemy team guessing at Sniper's real position. Sniper can ensure cart lanes and control points are clear, and can shut down flanking pick classes before they can attack his team's combo.
The objective is of particular interest to Sniper; he should focus on the cart on Payload maps and control points on Attack/Defense and KOTH maps. Important classes tend to gather around the objective, and killing them slows down the enemy's progress and opens up opportunities for your team to push in.