How Arcade Robot Combat Works

This guide describes the combat system the battle games on this site share, in more detail than the strategy guides do. The numbers quoted are the actual values the games use. It is aimed at players who want to know precisely what is happening rather than only what to do about it.

The four move profiles

Every attack in the system is built from one of four profiles, each defined by its timings, reach, arc width, damage and power cost.

Two patterns are worth noticing. First, the recovery is always longer than the active window, usually by two or three times - that asymmetry is what makes attacking a commitment rather than a free action.

Second, damage buys time. The heavy attack deals three times the light attack's damage and occupies more than twice as long in total. Nothing in the system is strictly better than anything else; each move trades one resource for another.

How hit quality is calculated

A hit is not simply a hit. The system computes a quality value between zero and one from two components, and that value drives both score and whether a hit counts as perfect.

Timing quality peaks at the centre of the active window and falls off toward both edges. A strike that connects halfway through its active frames scores the maximum; one that clips the first or last frame scores near zero on this component.

Distance quality peaks at roughly two thirds of the attack's reach. Connecting with the very tip or at point-blank range both score lower, which means there is a spacing sweet spot rather than simply 'as close as possible'.

The two are combined at sixty per cent timing and forty per cent distance. That weighting is a design statement: when you hit matters more than where you are, but both matter.

Open targets and why they matter so much

A target is 'open' when it is staggered, mid-wind-up or otherwise unable to respond. Hitting an open target doubles the damage and multiplies the score by roughly 1.6.

That is a large bonus and it is deliberately large, because it is the mechanism that rewards the behaviour the whole system is built around - waiting for the right moment rather than attacking whenever possible.

It also means target selection matters more than most players realise. A staggered enemy across the arena is frequently a better target than a healthy one beside you, purely on the arithmetic.

How an incoming attack resolves

When something hits you, the system checks conditions in a fixed order, and the order is deliberate.

• Boost invulnerability first. A commitment you already made should never be overridden by anything else.
• Then post-hit invulnerability, so a second hit in the same instant cannot land.
• Then the deflector, but only if the attack is blockable. If the plate went up inside the deflect window it is a deflect; otherwise it is a block.
• Then damage.

Checking boost invulnerability first matters more than it appears. If the deflector were checked first, a player who boosted and happened to be facing the right way would get a block instead of an evade - a worse outcome for having done something correct.

The deflector check also depends on facing: the plate covers a cone in front of the machine, so an attack arriving from behind ignores it entirely. Being flanked while blocking is a real failure state rather than a bug.

The angle convention

One detail that causes endless confusion in combat systems generally: an attack's angle is the direction the blow travels, not the direction it came from.

So an attack coming at you from the left has an angle pointing right. The attacker sits at the attack's angle plus 180 degrees as seen from you, and the deflector test compares your facing against that.

Getting this backwards produces a game where blocking works only when you face away from the attacker, which is the kind of bug that survives for a long time because it is hard to notice and easy to misattribute.

Why one attack cannot hit twice

A rule that sounds like an implementation detail and is in fact load-bearing for the whole combat system.

An attack's active window lasts around six frames. Its arc overlaps a target for most of them. Without a rule preventing it, a single swing would resolve a hit on every one of those frames - six times the damage, six times the score, and completely unpredictable, because the exact number would depend on how the target happened to be moving.

So each attack records what it has already struck and refuses to strike the same thing again. One press, one hit per target, regardless of how long the arc and the target overlap.

The consequence for a player is that there is nothing to gain from positioning so that your arc lingers on a target, and nothing to lose from clipping it briefly. What matters is whether the hit lands at all and how well-timed it was - which is exactly what the game is trying to measure.

It is also a rule that is easy to break by accident when writing a game, and the symptom is distinctive: enemies dying far too quickly and scores that are wildly inconsistent between similar-looking exchanges.

Frequently asked questions