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 6 to be safe — 5 if everyone is prepared

At level 40, a party of Volcanion's top six counters needs 4.49 trainers (round up: 5), and a mixed lobby of ranks 13-24 needs 5.33 (round up: 6). The raid timer is 300 seconds and one prepared trainer alone would take 20:40. No level in this range makes it soloable with a prepared party.

Volcanion · Elite

firewater

Weak to

groundrockelectric

Boss CP: 57,389
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 Volcanion 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	7(6.81)	8(7.41)	9(8.41)	34:07	6.0
Level 25	6(5.36)	7(6.18)	7(6.94)	28:25	6.0
Level 30	5(4.58)	6(5.16)	7(6.01)	23:44	6.0
Level 35	5(4.30)	5(4.73)	6(5.71)	21:45	6.0
Level 40	5(4.16)	5(4.49)	6(5.33)	20:40	6.0
Level 45	5(4.08)	5(4.27)	6(5.14)	19:38	6.0
Level 50	4(3.80)	5(4.06)	5(4.91)	18:40	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.

5 trainers at level 40

Zekrom4.16

A prepared party

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

5 trainers at level 40

Zekrom4.16
Zeraora4.49
Eternatus4.37
Landorus (Therian)4.67
Raikou4.66
Kyurem (Black)4.58

A mixed local group

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

6 trainers at level 40

Xurkitree5.17
Regigigas5.14
Mewtwo5.26
Rayquaza5.21
Keldeo5.22
Regieleki5.51

The party these numbers assume

1. Zekrom

Charge Beam + Fusion Bolt

2. Zeraora

Spark + Plasma Fists

3. Eternatus

Dragon Tail + Dynamax Cannon

4. Landorus (Therian)

Mud Shot + Sandsear Storm

5. Raikou

Thunder Shock + Wild Charge

6. Kyurem (Black)

Dragon Tail + Fusion Bolt

See the full ranked counter list for Volcanion · 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.