The flies
The four breeds
Direct, Cautious, Erratic and Bold, and what sets them apart.
Tuned, not trained
All four breeds share the same simulated brain design and the same fly body. What makes them different is a short list of numbers, from 0 to 1, that adjust how strongly the brain reacts to different things: how hard it pushes forward, how much it fears a hawk, how easily a lure distracts it, and so on. These numbers were hand-tuned by the team and checked by simulating many races. They were not trained or learned. Nothing about a breed changes during a race or between races.
The numbers on this page are the real tuning values from the simulation's breed files. Each breed was tuned so it genuinely suits some conditions and is hurt by others, which is what gives the form guide meaning.
The four breeds
Bars show each tuning value as a share of its 0 to 1 range (the number on the right is that value times 100). Hover a label for what it does. Click through to a breed's own page for its brain and live win rate.
Direct
The focused all-rounderDirect goes where it is pointed. It has the least interest in food and light lures, drives hard, and gets away reasonably fast, so it has no single glaring weakness on a clear track. Its low caution means it clips more hazards when a track is crowded with them, and its stamina is only middling, so very long races favour others.
Strengths
- Almost ignores lures (lowest distractibility of the four)
- Strong forward drive
- Good early pace without being a pure sprinter
Weaknesses
- Lowest caution: pays on hazard-heavy tracks
- Modest stamina, so it can run out of road in a marathon
Cautious
Slow away, hard to stopCautious pays a warm-up penalty in the opening moments, so it is often last off the line. But its energy lasts, and it shrugs off gusts that push other flies around. The longer the lane and the rougher the weather, the more that start matters less.
Strengths
- Highest stamina of the four
- Highest wind resistance: gales barely move it
- Steady through hazards
Weaknesses
- Slowest start by far (lowest early pace)
- Weakest in sprints, where there is no time to catch up
Erratic
The chaos merchantErratic is the long shot. Its brain is the noisiest and it is pulled hardest toward food and light, so a lure-heavy track can wreck its race. On a clear track, or when hawks swoop, its twitchy reactions turn into an advantage. Expect big swings from one race to the next.
Strengths
- Highest caution: recovers best from hazard hits
- Reacts hardest to hawks (highest fearfulness)
- Best finishing kick of the four
Weaknesses
- By far the most distractible: stops hard and often on lures
- Noisiest brain: a wobbly, high-variance line
- Low stamina and mid-low wind resistance
Bold
Sprint specialistBold blazes off the line and hopes the lane is short. Over a sprint on a calm day it is at its best. Stretch the distance, add wind, or send a hawk overhead, and it pays for the early burst.
Strengths
- Explosive start: the only breed with no warm-up penalty
- Strong forward drive
- Steadiest line (lowest noise)
- Ignores lures
Weaknesses
- Lowest stamina: fades over distance
- Lowest wind resistance: hates a gale
- Low fearfulness means hawk swoops rattle it
- Weakest finishing kick
What each trait does
| Trait | What it changes |
|---|---|
| Early pace | How well the fly gets going at the start. Low early pace pays a warm-up penalty in the first moments of the race. |
| Stamina | How slowly its energy drains. Energy drains every moment, faster when the fly runs hard, and a tired fly loses forward speed. Matters most over longer lanes. |
| Finishing kick | How well it closes. Every fly tires a little in the final fifth of the race. A strong kick buys relief from that, and the brain senses the late-sprint cue. |
| Drive | Called aggression in the tuning files. How strongly its brain pushes forward. |
| Wind resistance | How much of a gust actually lands on the fly, and how firmly its brain steers against drift. |
| Caution | How hard it steers away from hazards and rails, and how quickly it recovers after a hazard hit. |
| Lure pull | Called distractibility. How strongly food and light lures pull it sideways, and how long it stops when it lands on food. |
| Hawk reaction | Called fearfulness. How hard it turns away from a swooping hawk and bursts off. Low values mean it tends to freeze instead. |
| Jitter | Called noise. Random variation in its neurons, which makes its line less predictable. |
A tenth value, turn_smoothing, is set to 0.3 for every breed. It controls how quickly a fly's turning and speed ease toward what its brain asks for, and it is deliberately not a differentiator.
Under the hood the trait values act in two places. Some scale how strongly a given sense drives the fly's motor neurons (lure pull scales the food and light response, hawk reaction scales the predator response, wind resistance scales the wind counter-steer, finishing kick scales the late-sprint input). Others are body mechanics applied to every fly the same way (the energy reserve behind stamina and early pace, collision stun, wind drag). Read A fly and its brain to see where each sense enters.
Side by side
| Trait | Direct | Cautious | Erratic | Bold |
|---|---|---|---|---|
| Early pace | 0.60 | 0.12 | 0.35 | 1.00 |
| Stamina | 0.35 | 0.70 | 0.30 | 0.12 |
| Finishing kick | 0.50 | 0.50 | 0.55 | 0.32 |
| Drive | 0.85 | 0.55 | 0.68 | 0.85 |
| Wind resistance | 0.45 | 0.70 | 0.35 | 0.20 |
| Caution | 0.17 | 0.22 | 0.45 | 0.25 |
| Lure pull | 0.05 | 0.24 | 0.95 | 0.08 |
| Hawk reaction | 0.35 | 0.55 | 0.95 | 0.15 |
| Jitter | 0.15 | 0.15 | 0.24 | 0.10 |
Which conditions favour which breed, in one line each: Bold loves short, calm sprints; Cautious loves long races and gales; Direct likes clear and lure-heavy tracks over sprint and mile distances; Erratic is a high-variance pick that can shine with hawks about but struggles on a lure-heavy track. See Races and conditions for what each condition changes.