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 5 to be safe — 4 if everyone is prepared

At level 40, a party of Calyrex (Ice Rider)'s top six counters needs 3.57 trainers (round up: 4), and a mixed lobby of ranks 13-24 needs 4.91 (round up: 5). The raid timer is 300 seconds and one prepared trainer alone would take 16:24. No level in this range makes it soloable with a prepared party.

Calyrex (Ice Rider) · Elite

psychicice

Weak to

rockbugghoststeelfiredark

Boss CP: 64,657
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 Calyrex (Ice Rider) 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	5(4.74)	6(5.20)	8(7.72)	23:57	6.0
Level 25	4(3.86)	5(4.45)	7(6.26)	20:28	6.0
Level 30	4(3.56)	5(4.04)	6(5.54)	18:36	6.0
Level 35	4(3.40)	4(3.78)	6(5.21)	17:25	6.0
Level 40	4(3.09)	4(3.57)	5(4.91)	16:24	6.0
Level 45	3(2.97)	4(3.46)	5(4.69)	15:56	6.0
Level 50	3(2.93)	4(3.39)	5(4.53)	15:35	5.9

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.

4 trainers at level 40

Zacian (Crowned Sword)3.09

A prepared party

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

4 trainers at level 40

Zacian (Crowned Sword)3.09
Necrozma (Dusk Mane)3.14
Zamazenta (Crowned Shield)3.18
Necrozma (Dawn Wings)3.49
Metagross4.24
Reshiram4.26

A mixed local group

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

5 trainers at level 40

Dialga4.76
Hydreigon4.81
Eternatus4.84
Chandelure4.88
Giratina (Origin)4.90
Cinderace4.91

The party these numbers assume

1. Zacian (Crowned Sword)

Metal Claw + Behemoth Blade

2. Necrozma (Dusk Mane)

Metal Claw + Sunsteel Strike

3. Zamazenta (Crowned Shield)

Metal Claw + Behemoth Bash

4. Necrozma (Dawn Wings)

Metal Claw + Moongeist Beam

5. Metagross

Fury Cutter + Meteor Mash

6. Reshiram

Fire Fang + Fusion Flare

See the full ranked counter list for Calyrex (Ice Rider) · 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.