How to properly stat a Kamehameha or Heat Vision....

[Silverblade]

...and I don't mean the amounts of dice of damage.

I always struggle with statting those beam powers in GURPS - not because of damage, but to get their "feel" right.

How do you go about it?

Damage type is easy for heat vision (burning attack) but Anime super beams often seem like "concussive force blasts" - which must make them crushing and double knockback maybe?

Then, they're often continuous - characters will fire them often over several seconds, and sometimes seem to only be able to move the beam about slowly.

Rapid fire should cover it I think - but how much Rapid Fire causes an attack to be a beam? Does it at all? Often, these types of attack function more like a really long blade. Do you use Spraying Fire with high RoF for that? Is it really a Jet with a long range? Or is it even Cyclic?

Then, many of these beam attacks are fired over several seconds - is this just several single ranged attack maneuvers over several rounds? I think mechnically is must be - and the beam never really stopping or not being separated into different projectiles is just a special effect.

Next, I think I remember Goku firing Kamehamehas that, in a way, "explode" - and kind of not. The beam hits the ground and causes a giant blue bubble destroying everything at the point of impact - but is that an Explosion enhancement, or really an Area effect enhancement on his Crushing Attack? The former has different game effects (e.g. knockback from the point of impact) than the latter (which creates more like a death zone), I think. Not to mention that this type of beam manages to be both burning and crushing somehow, or one or the other at different times - or maybe even Corrosive? Sometimes it dissolves opponents, sometimes it just knocks them through the scenery.

How do all of you create a generic superheroic blast/beam attack?

[pawsplay]

Heat vision I would do as a tight beam burning attack. I would treat the way it tends to "lock on" as a feature of high Accuracy; you Aim, and then attack with it in successive rounds.

I think massive knockback might just be a feature of anime/manga combat. I guess one question is, is this just a visual style, or in terms of the outcome of the combat, is knockback really occurring? If so, I guess make it crushing, explosive optional, incendiary optional. Again, if it's depicted as a continuous beam, high Accuracy would represent an attack that "powers up" and then is used at full strength successively.

[Varyon]

Continuous Beam is something I've considered in the past, although that was more in terms of trying to figure out how to model Diablo III's wizard's Disintegration. Here's what I came up with as a sort of rough draft.

Continuous Beam: This variant of Cone changes your Innate Attack from a discrete projectile or blast into a continuous beam that is more effective the longer the target is within it. It costs +50%, with a further +10% per yard of width at the end of the cone. A 0 yard width option is available for the base +50% - this functions similarly to a 1-yard-wide cone, being able to strike any target in its path, but against foes other than the primary target skill is capped to 9 and the attack can be Dodged without needing to dive for cover or otherwise move out of your hex.

Continuous Beam gives a +4 to hit. However, at MoS 0 it only deals 10% of Injury; similarly, it only has 10% of any additional effects (knockback, starting fires, degrading armor, etc). Every +1 to MoS increases this by a further 10%, to a maximum of 100% with MoS 9 or higher. A target who successfully Dodges reduces this by MoS*20% (treat MoS 0 as 0.5, for -10%).

Continuous Beam functions similarly to Rapid Fire. You can opt to use it at a lower "rate of fire," reducing the bonus and the maximum effectiveness. The bare minimum is +1 and 25% for a blast that lasts only a quarter of a second; the bonus increases to +2 with a cap of 45%, +3 with a cap of 65%, and +4 with a cap of 85%. It is also subject to many of the rules from B408-410 - Rapid Fire vs Close Stationary Targets (treat it as having Rcl 1), Spraying Fire (lose 10% per yard traversed; you can assign less than 25% to any given foe when doing so, at which point you have no bonus to hit), and Suppression Fire (you can cover up to 4 zones at 25% each, as though you were using an RoF 20 weapon*) - as well as Follow-Up Shots (TS14) and Walking the Burst (TS16; note many such attacks should be treated as being all-tracers).

*If there are other relevant rapid fire rules that I missed, you can treat Continuous Beam as though it were RoF 1 per 5% of effectiveness.

...

As for the rest of the questions, what type of damage the beam deals depends on the source. Superman's heat vision is, obviously, Burning. A disintegration beam would likely by Corrosion. A ki blast like the Kamehameha or Ryu's Shinkuu Hadouken is typically going to be Crushing, although sometimes they're treated as though they had a heat component; arguably this would be Incendiary, but that doesn't scale with the power of the attack (it's always just +1 burning damage when what it probably should do is make some portion of the base damage be treated as though it were burning for purposes of Starting Fires). The explosion that large ki beams/blasts sometimes generate is arguably just what happens when a really powerful crushing attack strikes a surface (consider meteors); treating all crushing attacks as 5% explosive (so 1d per 20d) might not be terrible. If you want more of an effect, add Explosive to some or all of the damage.

[Donny Brook]

Another approach is the Jet modifier. Add Cosmic (Rule Excemption) to allow adding Rapid Fire or adapt normal melee Rapid Strike rules if you want damage to scale with success.

[Refplace]

Really its all about the modifiers here.
Immediate Preparation Required gets you that delay as they build up the power.
Increased Accuracy, probably. Variable.
Additional levels with Costs FP or Takes Extra Time.
Possibly based on ST using Weaponized or other modifiers.

I would just go through the list in Power-Ups Enhancements, checking off the ones that applied to the build I was looking for.