How the Five Dynamic AI Tiers Are Set: PPM, Thresholds, and Locking
Tier comes from the mean personal PPM of each human survivor. Thresholds recompute daily from server-wide data.
What PPM is and how it is computed
PPM is roughly score per minute. The system averages each human's personal PPM. It does not divide team score by total time. One new player will not punch the tier through the floor.
The default is the all-time board. An admin can switch to season data and require at least 300 season minutes so tiny samples do not bounce the tier.
Five tiers, thresholds recomputed daily
Auto mode only picks among the five tiers from Easy to Extreme. Cutoffs recompute daily from server-wide PPM at P60 / P75 / P90 / P95. If thresholds are missing or stale, it falls back to config defaults.
| Tier | Check window | Low SI Threshold | Scored candidates | Sweet Spot Width |
|---|---|---|---|---|
| Easy | 16s | 12% | 9 | 1.25x |
| Normal | 12s | 20% | 10 | 1.15x |
| Hard | 10s | 27% | 11 | 1.08x |
| Expert | 8s | 34% | 12 | 1.00x |
| Extreme | 6s | 50% | 12 | 1.00x |
The full countdown is 16 seconds on every tier. Higher tiers check earlier, allow a larger leftover-SI ratio, score more spawn candidates, and use a tighter distance sweet spot.
When the tier is set and when it locks
Inside the saferoom it is an estimate and recomputes when the roster changes. Leaving the saferoom locks the round. Joins and leaves mid-round do not flip the pressure. The next round estimates from the new team.
What a tier feels like in game
The tier feeds two systems. Spawn control decides when and where. The AI layer decides how SI fight after they spawn. Speed is what you feel first:
- Hunter / Jockey air speed：700 on Easy, 900 on Extreme.
- Bunnyhop Speed：Smoker 70 to 150, Boomer 70 to 250, Spitter 45 to 250.
- Tank bhop speed cap：700 up to 1050. A high-tier Tank on flat ground is almost impossible to lose.
The current auto config owns 97 cvars. Before a tier change it restores the baseline, then applies the target tier. Old values do not linger.
Common misconceptions about the tiers
- "My score is high, so I'm dragging the team up"
- It takes the arithmetic mean of individual PPM, not a team total. One high scorer raises the average, but bringing one newcomer into the four lowers it just as surely. Do not deliberately underplay to hold the tier down.
- "This round is too hard, let's swap someone in"
- It locks when you leave the saferoom, so swapping mid-round changes nothing. Adjustments have to wait for the next saferoom.
- "The same team wasn't this hard yesterday"
- Thresholds are recalculated daily from server-wide data. When everyone plays better, the dividing lines move up, and the same PPM can land in a lower tier today.
- "Higher tier just means more specials"
- The countdown is 16 seconds at all five tiers. What changes is an earlier check window, a higher share of specials allowed on the field, and more spawn candidates. The density feels higher, but the beat is the same.
- "It suddenly got harder halfway through"
- The tier is locked for the round. It getting harder usually means your own condition changed — someone on black-and-white, supplies gone, or the team stuck in place.
Above Extreme there is Neri
Auto PPM never picks tier 6. Neri only exists as a fixed mode: Extreme plus Anne-Neri. Hunter pounce interval and cooldown go to zero, Boomer can jump-vomit, Charger aim offset is 180, Tank bunnyhop chase range is maxed. Spawn timing stays Extreme: 6-second checks, 16-second countdown.