Team Attack

Team Attack, named Friendly Fire in Super Smash Bros. Melee, is an optional feature for Team Battles appearing in the Smash Bros. games. Normally, teammates are incapable of attacking or damaging each other, with attacks simply passing through them with no effect. Activating Team Attack disables this immunity, allowing teammates to hit or even KO each other.

On the surface, Team Attack has no advantages and is simply a hindrance (for example, teammates must get out of the way of projectiles). However, it does give rise to some new strategies:
 * Teammates can be healed by using an energy projectile and PSI Magnet or Absorbing Vortex, or can use Oil Panic or Pocket to capture friendly projectiles. (However, in Super Smash Bros. 4 as of version 1.1.3, these moves are much weaker when used this way.)
 * Teammates can be used as ammunition when thrown or spat, and their neutral special can be copied by a friendly Kirby.
 * Teammates can attack recovering friendlies to allow the re-use of a triple jump or even knock them towards the stage.
 * Teammates can attack each other to replenish their stale attacks or knock them out of ending lag (for example, jabbing a Jigglypuff that has used Rest in order to let them act much earlier).

The vast majority of tournaments for every game require that Team Attack be turned on. This ensures that teammates cooperate a lot more with each other and ensures that 2v1 strategies aren't as lopsided.

In most one-player modes, Team Attack is turned off so players and enemies cannot hit their teammates.

Some moves and Final Smashes can affect teammates whether Team Attack is on or off. These include:
 * Projectile or item attacks that can damage the user, such as most explosives.
 * Puff Up can and will push and KO teammates.
 * Galaxia Darkness will damage teammates with the weaker hit. This oddity was removed in SSB4.
 * Landmasters cannot directly damage teammates, but they will obstruct them and can KO them by flying them off the screen.
 * Similarly, Iceberg will obstruct teammates without dealing damage.
 * End of Day does not directly damage teammates, but the screen-scrolling effect makes it difficult to move and causes a few points of hoop damage.

If Team Attack is enabled, the Team Healer will consider any teammate an enemy, which means it will either heal them for 11%, or damage them for 8%. Leaving the option turned off does not affect the bonuses Bully, Predator, and Stalker; even though teammates are immune to one's attacks and so the only viable target is the opponent, these single-target-penalizing bonuses still activate in 2-on-1 or 3-on-1 matches.

Trivia

 * In every game, CPUs will ignore Team Attack, throwing and pummeling teammates when they are grabbed on accident, as well as using powerful attacks even if a teammate at KO percentage is in the way.