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 2 to be safe — 2 if everyone is prepared

At level 40, a party of Cranidos's top six counters needs 1.18 trainers (round up: 2), and a mixed lobby of ranks 13-24 needs 1.58 (round up: 2). The raid timer is 300 seconds and one prepared trainer alone would take 5:26. No level in this range makes it soloable with a prepared party. A duo works from level 20.

Cranidos · Elite

rock

Weak to

fightinggroundsteelwatergrass

Boss CP: 30,557
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 Cranidos 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	2(1.45)	2(1.73)	3(2.32)	7:57	6.0
Level 25	2(1.28)	2(1.49)	2(1.95)	6:50	6.0
Level 30	2(1.12)	2(1.31)	2(1.74)	6:01	5.8
Level 35	2(1.09)	2(1.25)	2(1.66)	5:44	5.8
Level 40	2(1.04)	2(1.18)	2(1.58)	5:26	5.7
Level 45	2(1.02)	2(1.13)	2(1.53)	5:12	5.5
Level 50	1(0.98)	2(1.09)	2(1.47)	5:02	5.4

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

Zamazenta (Crowned Shield)1.04

A prepared party

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

2 trainers at level 40

Zamazenta (Crowned Shield)1.04
Zacian (Crowned Sword)1.04
Necrozma (Dusk Mane)1.13
Keldeo1.18
Lucario1.32
Kartana1.39

A mixed local group

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

2 trainers at level 40

Necrozma (Dawn Wings)1.54
Hisuian Decidueye1.55
Urshifu (Single Strike)1.57
Conkeldurr1.57
Urshifu (Rapid Strike)1.57
Zarude1.58

The party these numbers assume

1. Zamazenta (Crowned Shield)

Metal Claw + Behemoth Bash

2. Zacian (Crowned Sword)

Metal Claw + Behemoth Blade

3. Necrozma (Dusk Mane)

Metal Claw + Sunsteel Strike

4. Keldeo

Low Kick + Secret Sword

5. Lucario

Force Palm + Aura Sphere

6. Kartana

Razor Leaf + Sacred Sword

See the full ranked counter list for Cranidos · 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.