Normal Shot: Flash Shot: A standard buster shot, now with extra hitstun. Flash man can have 4 shots on screen - it'll be difficult for your opponent to dodge all of them. Deals 2 damage.
Special 1: Flash Gatling: Flash Man stops in place, and fires off 6 shots in rapid succession in 3 different angles, costing 5 EP. These do 3 dmg and hit through opponents. This attack can be aimed upwards too.
In air, Flash Gatling functions as a double jump - Flash Man fires 3 bullets downward, propelling him upwards. It costs 3 EP and does 3 dmg. Keep in mind you can only use this once every time you become airborne, unless you get hit - then you can use it once again.
Special 2: Time Stopper: The one you've been waiting for. Time Stopper costs half of your total EP (14 EP), to freeze your enemies in place. If you hold up or down when starting Time Stopper, you'll get a shorter/longer Time Stopper respectively, with a shorter/longer start up as well.
Time Stopper freezes enemies in their current state - however projectiles are not affected, so you'll still have to dodge those. Flash Shot, however, when fired in the Time Stopper state, is frozen as well, and gains the combo state.
Other: Flash Man is an ice character, so he gets a fast wavedash. Don't object, fast wavedashes are pretty nice.
Flash Man can pull off big damage with his Time Stopper comboes, up to 11 if you manage to use Gatling to knock an opponent into your Flash Shots.
Flash Shots don't combo when they overlap, so don't spam all of your shots in Time Stopper.
Flash Gatling is useful for opponents in an area you can't reach, although this is better reserved for opponents with already low health, since you'll want to save EP for your Time Stopper comboes.
You can also use Gatling in air if your opponent is below you, or use it to dodge an incoming projectile.
Flash Shot has enough hitstun to go into a Time Stopper, although be wary of hitstun cancels.
Wavedash away from opponents who fare better up close - it's faster than walking.
You can use Time Stopper when some one's respawned - just make sure you time it well - too early and they'll stay spawning in, meaning you've wasted your Time Stopper.
Some opponents can become invulnerable, deflect projectiles, or just be out of your reach - using Time Stopper carelessly on these targets means you'll have wasted 14 EP, don't do it. Special mention goes out to Charge Man.
Opponents stuck in Time Stopper will become unstuck when hit. A stray NS from earlier can ruin your Time Stopper, be careful.
Some characters can go into a state where they become immune to hitstun. Although they can still take combo damage, they can dodge some of it, not being stunned by your shots.
Hard Man is particularly notable, never taking hitstun (except from grabs, which you don't have).
Hitboxes don't disappear when Time Stopper is used, because physics is a myth. This includes physical hitboxes, so be wary of dives, tomahawks, swords and combusting robots.