Group size estimator

How many trainers do I need to invite?

The Estimator is already "trainers of this attacker needed to finish inside the timer", so this page does not invent a number: it reads it off the boss's own ranked counter list for three realistic parties and re-simulates each of them at every level from 20 to 50.

Raid bossTierIVsWeatherFriendshipDodgingShadow attackersMega attackersLegendary attackers

Invite 4 to be safe — 3 if everyone is prepared

At level 40, a party of Rayquaza's top six counters needs 2.28 trainers (round up: 3), and a mixed lobby of ranks 13-24 needs 3.12 (round up: 4). The raid timer is 300 seconds and one prepared trainer alone would take 10:31. No level in this range makes it soloable with a prepared party.

Rayquaza · Elite

dragonflying

Weak to

icerockdragonfairy

Boss CP: 57,513
Boss HP: 20,000
Raid timer: 300s
Party used: 6

Trainers needed, by attacker level

Scroll sideways for the mixed-lobby column.

Trainers needed to beat Rayquaza at each attacker level
Attacker level	Six of the best counter	A prepared party	A mixed local group	Prepared solo time	Faints per timer
Level 20	4(3.06)	5(4.13)	6(5.11)	19:00	6.0
Level 25	3(2.58)	4(3.49)	5(4.12)	16:03	6.0
Level 30	3(2.31)	3(2.83)	4(3.52)	13:00	6.0
Level 35	3(2.22)	3(2.63)	4(3.33)	12:07	6.0
Level 40	2(1.81)	3(2.28)	4(3.12)	10:31	6.0
Level 45	2(1.67)	3(2.19)	4(3.01)	10:04	6.0
Level 50	2(1.55)	3(2.05)	3(2.91)	9:26	6.0

Whole trainers in bold, the raw estimator in brackets — 2.04 means two trainers is right on the line and three is comfortable.

Six of the best counter

Every trainer brings six copies of the single best counter — the theoretical floor.

2 trainers at level 40

Kyurem (White)1.81

A prepared party

Each trainer brings the boss's top six counters, powered up and correctly TM'd.

3 trainers at level 40

Kyurem (White)1.81
Kyurem (Black)2.01
Eternatus2.24
Mamoswine2.44
Galarian Darmanitan (Standard)2.59
Glaceon2.62

A mixed local group

Ranks 13-24: reasonable but unoptimised parties, which is what a public lobby usually is.

4 trainers at level 40

Dialga (Origin)2.90
Zamazenta (Crowned Shield)2.99
Avalugg3.03
Articuno3.06
Zacian (Crowned Sword)3.08
Hisuian Avalugg3.12

The party these numbers assume

1. Kyurem (White)

Ice Fang + Ice Burn

2. Kyurem (Black)

Dragon Tail + Freeze Shock

3. Eternatus

Dragon Tail + Dynamax Cannon

4. Mamoswine

Powder Snow + Avalanche

5. Galarian Darmanitan (Standard)

Ice Fang + Avalanche

6. Glaceon

Frost Breath + Avalanche

See the full ranked counter list for Rayquaza · check a real lobby (win chance, who brings what) · make a share card of the top six

How this is worked out

The boss is ranked once at level 40 with rankCached (the same memoised call /raids makes), then the three bands — rank 1, ranks 1-6, ranks 13-24 — are re-simulated at each attacker level with an 8-run Monte Carlo each. Holding the party fixed and moving only its level is deliberate: it answers "what if my party were level 20" rather than "what would a level-20 player's completely different party be", and it is about ten times cheaper than re-ranking every attacker seven times. The Estimator itself is Pokebattler's definition, time to win including rejoin time divided by the raid timer.