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 — 1 if everyone is prepared

At level 40, a party of Zamazenta (Crowned Shield)'s top six counters needs 1.00 trainers (round up: 1), and a mixed lobby of ranks 13-24 needs 1.23 (round up: 2). The raid timer is 180 seconds and one prepared trainer alone would take 2:55. A prepared solo becomes possible at level 40. A duo works from level 20.

Zamazenta (Crowned Shield) · Tier 3

fightingsteel

Weak to

fightinggroundfire

Boss CP: 27,859
Boss HP: 3,600
Raid timer: 180s
Party used: 6

Trainers needed, by attacker level

Scroll sideways for the mixed-lobby column.

Trainers needed to beat Zamazenta (Crowned Shield) 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(1.38)	2(1.57)	2(1.90)	4:35	6.0
Level 25	2(1.22)	2(1.32)	2(1.60)	3:52	6.0
Level 30	1(0.95)	2(1.12)	2(1.39)	3:17	5.9
Level 35	1(0.93)	2(1.05)	2(1.31)	3:04	5.8
Level 40	1(0.88)	1(1.00)	2(1.23)	2:55	5.5
Level 45	1(0.83)	1(0.95)	2(1.19)	2:47	5.1
Level 50	1(0.81)	1(0.93)	2(1.13)	2:44	5.1

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.

1 trainer at level 40

Keldeo0.88

A prepared party

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

1 trainer at level 40

Keldeo0.88
Blacephalon0.91
Terrakion1.01
Reshiram1.04
Lucario1.06
Landorus (Therian)1.07

A mixed local group

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

2 trainers at level 40

Groudon1.20
Urshifu (Rapid Strike)1.20
Emboar1.22
Conkeldurr1.22
Delphox1.23
Entei1.24

The party these numbers assume

1. Keldeo

Low Kick + Secret Sword

2. Blacephalon

Incinerate + Mind Blown

3. Terrakion

Double Kick + Sacred Sword

4. Reshiram

Fire Fang + Fusion Flare

5. Lucario

Force Palm + Aura Sphere

6. Landorus (Therian)

Mud Shot + Sandsear Storm

See the full ranked counter list for Zamazenta (Crowned Shield) · 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.