Editing PK Flash

When the move is initiated, Ness enters a hunched-over pose and shouts "PK Flash!" A ball of green light then appears above him. As the special move button is held, the ball of light moves downwards in an arching motion and increases in power, until the special button is released or until it is fully charged, at which point it explodes.

PK Flash can be charged until it falls to the altitude from where Ness initiated the attack. It can be steered horizontally by a considerable amount and vertically to a much lesser extent by using the control stick. In ''Melee'', ''Brawl'', and ''Smash 4'', if the attack falls upon a platform or a higher level of a stage before it is detonated, it will disappear harmlessly. This can be a problem, especially in ''Brawl'', since it falls below Ness' height when fully charged (but nonetheless, it is still considered fully charged if the player lets go of the special button right before it hits the ground). The ball of light is easier to control in was relatively difficult to control in ''Melee'', but was made easier to steer in future titles. In ''Ultimate'', it can cover more vertical distance than all other games, but it has slightly less kill power.

In all games except ''Ultimate'', when performed in the air, it puts Ness into a [[helpless]] falling animation. At no charge, it deals 11%{{GameIcon|SSBM}}{{GameIcon|SSBU}}/9%{{GameIcon|SSBB}}{{GameIcon|SSB4}} and when fully charged (without the influence of special conditions) it deals a maximum damage of 36%{{GameIcon|SSBM}}/37%{{GameIcon|SSBB}}{{GameIcon|SSB4}}/27%{{GameIcon|SSBU}} with huge knockback. Of all projectiles, PK Flash has the highest knockback when fully or almost fully charged, and KOs as low as 60%. In ''SSB4'', PK Flash covers more range behind Ness, whereas in previous games PK Flash has reduced range if shifted behind.

Prior to ''Ultimate'', due to the move's lag and the fact that it leaves Ness vulnerable, most players often avoid using this attack. However, it does have some niche utility. For example, it can be used for low percentage Star KOs when used on an opponent that is landing or as a risky but effective burst options on opponents recklessly jumping in. In addition, it can also be used for edgeguarding, attacking recovering opponents, and/or gimping their recoveries, though all of this is less effective compared to other moves. In ''Ultimate'', thanks to its improvements PK Flash has more utility, such as allowing players to use its uncharged variant to extend some combos and stall in the air as it does not leave Ness in a helpless animation anymore.

The move also has good uses in Team Battles. It can be absorbed three times (or once in ''SSB4'') by Mr. Game and Watch's [[Oil Panic]], giving him a OHKO. It can also be used for healing a Lucas, another Ness or a Mii Gunner by having them use [[PSI Magnet]] or [[Absorbing Vortex]], on it. Finally, Ness' teammate can grab his opponent, allowing Ness to use his fully charged PK Flash.

''Melee''{{'}}s PK Flash, used by both Ness and Kirby, can be [[PK Trap glitch|subcharged]] due to a [[glitch]] that occurs when characters transition between ground and air.

Originally, in ''Melee'', the attack is colored green, while in ''Brawl'' and ''SSB4'', it is given more of a blueish tint.

Due to Ness's accent, many players mishear "PK Flash" as any of a variety of phrases, such as "PK Pulse" and "PK Cross", as the final "sh" sound is quieter than the rest of the yell. However, when [[Kirby]] copies Ness, he clearly says "PK Flash" when he uses it, despite both characters having the [[wikipedia:Makiko Ōmoto|same voice actress]]. In ''Smash 4'', due to Ness's new voice clips, PK Flash is now heard correctly.

[[File:PK Flash.gif|thumb|190px|Ness (named “Nass” by the player) using PSI Flash α in ''EarthBound''.]]

PK Flash (localized as PSI Flash in ''{{b|EarthBound|game}}'') first appeared in ''{{b|EarthBound|game}}'' and later appeared in ''{{s|wikibound|Mother 3}}''. In both games, the move involved using the character's psychic power to cause a strong flash of light that could affect all enemies. In ''EarthBound'', Ness learns PK Flash. There are four levels to this power, which are: α (Alpha), β (Beta), γ (Gamma), and Ω (Omega). PK Flash α will only cause enemies to cry or feel strange. PK Flash β can also cause enemies to feel numb or be instantly destroyed. PK Flash γ and Ω each increase the chance of more powerful effects and decrease the chance of weaker ones. When Ness uses PK Flash in ''Smash'', the player can either let PK Flash fully charge and "explode" or stop charging early for a less powerful explosion. PK Flash being weaker when less charged and most powerful when fully charged is likely a reference to the different levels of PK Flash in ''EarthBound'', considering there are four different audio cues the detinating portion of the move can make depending on the charge starting in ''Smash 4''.