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I enjoyed playing sniper in TF2 although I don't have long sniper play time. I only use him in defensive situations, main because my map knowledge on sniper is poor, which makes me unable to quickly find vantage points during offense as a sniper. And my fear of backstabs force me to choose other classes if the enemy team have spies. Aiming skills cannot be taught as instinct must be obtained through practice. But some ideas and concepts can be learnt.
Tips:
-You are a sniper inside a multiplayer battle, not those singleplayer games. You are not sniping people from a mile away without moving. In TF2 you should be constantly moving from point to point to take down enemies by surprise. No matter how subtle you act, if you stand in the same place after taking a kill, some enemies will eventually notice that and pay you a visit. Being mobile is a key to success. Strike enemies from different directions, this strategy is particularly effective with two snipers. Your job is to bring down high priority targets, confuse the enemy, and create tension/pressure on their team.
-Aim for headshots. Besides dealing crit on a target, headshots are more stable to aim than bodyshots, when an enemy rotate their view, the area of body below their head will change according to their direction of vision. However, the surface of their head will remain the same size. So try to aim for headshots even it is harder to hit in the beginning.
-Use bows for close/mid-range combat. The tunneling vision of sniper rifle obstruct your view a lot, and your rifle also have a laser which tells the enemy your direction of aiming. Bows also have a faster charging time than rifle. Additionally, the taunt of bows are in fact a feasible way to kill an enemy due to the quick reaction of it. Taunt of bows is great for melee range duel if you can't win it with normal attacks.
My Builds:
Machina + Cozy Camper + Tribalman's Shiv
This build is for long range sniping only. Close range combats should be avoided at all cost due to the lack of damage output items besides the sniper rifle. Machina is good at long range camping as its damage when fully charged is insane. A body shot can almost kill a full 175 health class. And no one can withstand its fully charged headshot (with the exception of a heavy using fists of steel). But unable to perform no-scope shots make close range combat very demanding. Cozy camper allow you to continue on your job even enemies fire distractive shots far away, and it generate health which is useful for this build as you usually work alone. The tribalman's shiv gives you the ability to spy check efficiently, it is useful when you snipe alone.
Sydney Sleeper + Jarate + Bushwacka
This is a supportive build. Use sydney sleeper on enemies during a small fight to help your teammates far away (remember to have 50% of charge). The mini-crits are devastating in close range combats, and the rifle itself deals a nice amount of damage too. In team fights, throw jarate to coat enemies, then either rush in and use bushwacka or walk away and snipe them. I personally prefers the former one as a sniper don't have significant effect on a team after winning a team fight, so I would make a suicide attack to finish the fight earlier and earn my team more time to advance.
Hitman's Heatmaker + Darwin's Danger Shield + Kukri
This build is only suitable for expert players. Your overall damage will have a great boost with hitman's heatmaker only if you are superb at scoring headshots. The focus mode increase the fire rate a lot due to no unscoping for two shots and
