Bomb mechanics research

[Porcupine]

I got sidetracked and postponed this for a long time, but welcome to the first of hopefully many topics containing frame data.

Bombs work in a more complex way than ordinary projectiles. Technically they are just a projectile that makes an explosion at the end. The ones that make big and long-lasting explosions are what we tend to think of as bombs, which I focus on here. Explosions generally have priority and damage that is different from the projectile itself. I investigated the priorities in another thread.

The explosion detonates when the projectile reaches the end of its lifespan (in midair) or hits something (the ground, an obstacle, the edge of the stage, or the opponent) or when it reaches a certain distance to the center of the opponent VR, which I call the trigger radius. The trigger radius varies with each individual bomb attack and is mostly only featured in VOOT. It works three dimensionally, taking height into account.

In order for the explosion to be relevant, the projectile must have some way to detonate without hitting the opponent directly. Take for example Fei-Yen's CW hearts. Many of them make explosions similar to Temjin bombs, but they have no special way to detonate so Fei-Yen hearts tend to function as ordinary projectiles. Bombs typically detonate via the trigger radius or by ramming into the ground, which happens naturally for projectiles with a predetermined vertical arc and range.

I won't be studying the predetermined throwing arcs here as they can be seen and judged with your eyes. Most bombs in VOOT have enough throwing distance that if they do not detonate via the trigger radius, they will not be in a position to provide a helpful shield. Therefore, a useful tactic in VOOT is juking bombs, namely dodging the projectile cleanly enough to stay out of the trigger radius, causing the projectile to be thrown into oblivion, or at least behind you.

Having a large trigger radius is thus usually a benefit for defensive purposes. For offensive purposes, setting aside the hitting ability (speed and homing) of the projectile itself, a large trigger radius can either help or hurt, depending on how fast the explosion expands. I researched the trigger distances and frame data from detonation to impact for most bomb attacks in the following table. From those values the speed of the explosion wave can be inferred.



I tested all values in black, not necessarily accurately, using various methods. Values in gray are guesses, extrapolated from other attacks. Due to discreteness and changing positions, the impact frames can vary slightly. I listed the typical value and/or low end of the frame results.

Temjin/Apharmd bombs are actually made out of 4 separate expanding spheres. The first sphere is a large white flash which most people don't notice. The second and third spheres are what we see, and may be what counts for blocking shots. The fourth sphere is invisible, smaller, expands slower, and is what counts for hit detection. The blast radius was measured for the invisible sphere. A number in parenthesis is the estimated size of the visible sphere.

The first and second spheres appear on frame 1. The fourth sphere appears on frame 3, which is the earliest I've been able to hit an opponent with the explosion. Point-blank bombs usually hit on frame 4. If you manage to protrude your fist into their body then the projectile itself can hit on frame 1. The damage in that case is usually lower, often 1% or zero damage. At normal distances you have more frames to escape. The expanding wave of Temjin's bombs can be easily outrun.

Each segment of Apharmd/Grys-Vok forward-traveling napalm is different from how it looks. The fiery wall only appears on frame 6. From frame 1 through frame 6 there is a small white hump that flashes by briefly. It reaches its maximum size on frame 5. The actual explosion for hit detection is invisible, and appears on frame 2 already at full size, bigger than the white hump. This is why air dash napalm is undodgeable up close.

Grys-Vok crouching napalm and similar moves produce explosions that are effectively one segment of regular napalm followed by an elongated bomb. The two parts have the same damage. Apharmd LTLW explosion is identical in appearance (except for looking smoother due to higher polygon count) but the napalm part is not active.

[Porcupine]

In Force it seems no bombs have a trigger radius, and many do essentially no damage and expand extremely slowly, so they have minimal impact on the game. Some bombs do damage as direct attacks, but as long as you dodge the projectile you usually don't have to worry about the explosion.

In VOOM, most bombs do not have a trigger radius, except for Temjin crouching LW which is glitched. It has a whopping trigger radius of 70m which is the size of the explosion itself. Unlike VOOT, this trigger radius does not work three dimensionally. The bomb explodes when the projectile reaches within 70m of the opponent horizontally. Vertically, the projectile must be at the same height as the opponent (between knee and shoulder) to trigger an early detonation. If it hasn't triggered while airborne it will just roll on the ground and explode at its default spot.

In practice what this means is that Temjin crouching LW can be thought of as an energy blast that emanates from his body itself, striking 70m in all directions from where he stands, even behind him. So it is like a close combat attack, or anti-close combat attack. It also does huge damage and knocks away most VRs. The opponent can prevent crouching LW from triggering by jumping, or at specific distances by running under the arc.

Though they have no trigger radius, dash bombs are thrown for very short distances in VOOM, providing reliable shields anyway. They are a bit similar to Stein-Vok dash bombs in VOOT, except they do way more damage so are good for both offense and defense. VOOM Apharmd throws his bombs slightly farther than Temjin and in particular throws standing LW a long way, making it occasionally useable like a prediction laser if he loses his lock-on. Apharmd crouching LW does not have the trigger glitch, but it can still be used in close combat if the opponent is in front of him. (Crouching shots can be fired at close combat range in VOOM, like LT shots in VOOT).

VOOM bomb explosions are hemispheres that expand at medium speed, just as they appear. There are actually two hemispheres, a slightly smaller one appears inside the first one after half a second. If very unlucky it is possible to be double hit if you stand still at the edge of the blast.