Sprays are fun player-chosen pictures you can post in Team Fortress 2 (or pretty much any other source game). As it would suggest, the character “sprays” them on the wall like they’re graffiti, and to a lot of people they’re treated not much better. However sprays can have some effective (and rather sneaky) uses.
Mimicking hazards to the enemy
A wavering sniper dot, a crouched pyro near your sentry, a sticky trap…it won’t fool everyone, but it may cause your more gullible enemies to pause before turning that corner. Make sure you’re using the correct color for your team.
Alternatively, lure an enemy into a trap with a fake health kit or ammo box.
Warning teammates of upcoming dangers
Is a sentry around the corner? Is the payload pushing up to the map’s most popular sniper line? Warn your teammates, as well as the enemy team once you switch sides next round!
An example of one such spray, taken during an ultra-serious competitive matchup. Spray taken from a now-deleted SPUF post by govadina
Helpful guides for teammates
This one is mostly useful for Engineers, as they’re very reliant on teammates spy-checking and defending. However any class can benefit from posting reminders to their teammates.
Spray by “TheWhaleOilKing”, though sigtot made one without spelling errors that can be found here.
Some of the users reading your spray might play better at Team Fortress 2 for the rest of their lives!
One that might save you a lot of grief is a teleporter priority list, though as this example picture shows, scouts are free to ignore it.
‘Hot girl backstabbing’
This is one of the most infamous ways to get easy kills with sprays. Play cloak-and-dagger spy, spray a hot chick on the wall, backstab people whenever they stop to look at it. Here’s a demonstration video:
Obviously none of these are game-changing advantages, but considering that the normal tactical benefit of sprays lies somewhere between “useless” and “covering other people’s sprays,” these aren’t too bad.