Reactions and Perceptions

Reactions in Fiction

In fictional works, the ability to move across long distances differs significantly from the ability to move within shorter, "combat distances," leading to notable discrepancies when assessing a character's overall speed. To address these differences, this framework distinguishes between various types of speed, such as reaction speed and perception speed.

Reaction Speed

Reaction speed refers to a single, rapid movement performed within a defined timeframe, representing a character’s ability to respond instantaneously to a stimulus. This is distinct from combat speed, which involves a series of movements within similar timeframes. Examples of reaction speed include dodging bullets or evading fast-moving vehicles. Human benchmarks for reaction speed range from 300 milliseconds (below-average human) to 100 milliseconds (peak human). Reflexive, autonomous bodily responses can occur as quickly as 40 milliseconds, though these are not always applicable to reaction feats.

Perception Speed

Perception speed measures a character's ability to process sensory information quickly. Unlike reaction speed, it focuses on the intake of data rather than any subsequent physical response. This means a character might perceive an event without being able to react to it physically. For instance, a character with high perception speed might notice an incoming attack without having the reaction speed to dodge it.

Rules for Reaction Speed and Scaling

1. Distance and Timeframe: Reaction speed calculations must include both a distance and a timeframe component. Arbitrarily assuming a 1-meter distance for timeframe-based speed calculations is incorrect. Similarly, perception time is a timeframe measurement and not inherently proportional to speed unless supported by a specific feat.
2. Perception Speed Ratings: If only a timeframe is known (e.g., for characters who don’t require movement to attack or defend), perception speed should be rated based on the timeframe alone.
3. Scaling Rules:
   • If Character A can blitz Character B, A’s movement speed can scale to B’s reaction speed.
   • If Character A and Character B are considered combat equals, their reaction speeds may scale unless evidence suggests otherwise.
   • Other reaction speed scalings are situational and must be reviewed by experts or moderators.

Calculating Perception Time

To determine perception time, you must estimate the timeframe during which a character processes information or mentally reacts. This typically involves:

• Measuring the distance between the object and the character at two points: when the object first becomes perceivable and when the character initiates a reaction.
• Using the speed of the object, which should be reliably calculated or stated. Avoid compounding calculations (calc stacking).

Use this formula:

Perception Time (seconds)=Speed (meters/second) (Initial Distance - Reaction Distance)​

This method is most effective for feats where a character reacts to a projectile or object that is faster than them but at close-range distances.

Perception Time Levels

	Seconds in Standard Form	Seconds in Scientific Notation	SI Units
Below Average Human perception	0.2 and above	2×10-1 and above	200 Milliseconds and above
Average Human perception	0.2 - 0.13	2×10-1 - 1.3×10-1	200 Milliseconds to 130 Milliseconds
Athletic Human perception	0.13 - 0.1	1.3×10-1 - 1×10-1	130 Milliseconds to 100 Milliseconds
Peak Human perception	0.1 - 0.08	1×10-1 - 8×10-2	100 Milliseconds to 80 Milliseconds
Superhuman perception	0.08 - 0.0291	8×10-2 - 2.91×10-2	80 Milliseconds to 29.1 Milliseconds
Subsonic perception	0.0291 - 0.00583	2.91×10-2 - 5.83×10-3	29.1 Milliseconds to 5.83 Milliseconds
Subsonic+ perception	0.00583 - 0.0032	5.83×10-3 - 3.2×10-3	5.83 Milliseconds to 3.2 Milliseconds
Transonic perception	0.0032 - 0.00265	3.2×10-3 - 2.65×10-3	3.2 Milliseconds to 2.65 Milliseconds
Supersonic perception	0.00265 - 0.00117	2.65×10-3 - 1.17×10-3	2.65 Milliseconds to 1.17 Milliseconds
Supersonic+ perception	0.00117 - 0.00058	1.17×10-3 - 5.8×10-4	1.17 Milliseconds to 580 Microseconds
Hypersonic perception	0.00058 - 0.000294	5.8×10-4 - 2.94×10-4	580 Microseconds to 294 Microseconds
Hypersonic+ perception	0.000294 - 0.000117	2.94×10-4 - 1.17×10-4	294 Microseconds to 117 Microseconds
High Hypersonic perception	0.000117 - 0.0000588	1.17×10-4 - 5.58×10-5	117 Microseconds to 55.8 Microseconds
High Hypersonic+ perception	0.0000588 - 0.0000294	5.58×10-5 - 2.94×10-5	55.8 Microseconds to 29.4 Microseconds
Massively Hypersonic perception	0.0000294 - 0.00000294	2.94×10-5 - 2.94×10-6	29.4 Microseconds to 2.94 Microseconds
Massively Hypersonic+ perception	0.00000294 - 0.0000003336	2.94×10-6 - 3.336×10-7	2.94 Microseconds to 333.6 Nanoseconds
Sub-Relativistic perception	0.0000003336 - 0.0000000667	3.336×10-7 - 6.672×10-8	336 Nanoseconds to 66.72 Nanoseconds
Sub-Relativistic+ perception	0.0000000667 - 0.00000003336	6.67×10-8 - 3.336×10-8	66.72 Nanoseconds to 33.36 Nanoseconds
Relativistic perception	0.00000003336 - 0.00000000667	3.336×10-8 - 6.67×10-9	33.36 Nanoseconds to 6.67 Nanoseconds
Relativistic+ perception	0.00000000667 - 0.000000003336	6.67×10-9 - 3.336×10-9	6.67 Nanoseconds to 3.336 Nanoseconds
Speed of Light perception	0.000000003336	3.336×10-9	3.336 Nanoseconds
FTL perception	0.000000003336 - 0.0000000003336	3.336×10-9 - 3.336×10-10	3.336 Nanoseconds to 333.6 Picoseconds
FTL+ perception	0.0000000003336 - 0.00000000003336	3.336×10-10 - 3.336×10-11	333.6 Picoseconds to 33.36 Picoseconds
Massively FTL perception	0.00000000003336 - 0.000000000003336	3.336×10-11 - 3.336×10-12	33.36 Picoseconds to 3.336 Picoseconds
Massively FTL+ perception	0.000000000003336 and below	3.336×10-12 and below	3.336 Picoseconds and below