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 — 5 if everyone is prepared

At level 40, a party of Zamazenta's top six counters needs 4.15 trainers (round up: 5), and a mixed lobby of ranks 13-24 needs 4.79 (round up: 5). The raid timer is 300 seconds and one prepared trainer alone would take 19:07. No level in this range makes it soloable with a prepared party.

Zamazenta · Elite

fighting

Weak to

flyingpsychicfairy

Boss CP: 60,270
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 Zamazenta 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(6.43)	7(6.43)	8(7.72)	29:36	6.0
Level 25	5(4.91)	6(5.32)	7(6.40)	24:30	6.0
Level 30	5(4.25)	5(4.61)	6(5.54)	21:13	6.0
Level 35	5(4.11)	5(4.39)	6(5.13)	20:13	6.0
Level 40	4(3.90)	5(4.15)	5(4.79)	19:07	6.0
Level 45	4(3.81)	5(4.03)	5(4.65)	18:34	6.0
Level 50	4(3.62)	4(3.82)	5(4.49)	17:35	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.

4 trainers at level 40

Mewtwo3.90

A prepared party

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

5 trainers at level 40

Mewtwo3.90
Enamorus (Incarnate)3.97
Galarian Articuno4.18
Rayquaza4.25
Moltres4.29
Zacian (Crowned Sword)4.33

A mixed local group

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

5 trainers at level 40

Lugia4.57
Zamazenta (Crowned Shield)4.61
Eternatus4.64
Hoopa (Unbound)4.69
Braviary4.70
Lunala4.76

The party these numbers assume

1. Mewtwo

Confusion + Psystrike

2. Enamorus (Incarnate)

Fairy Wind + Fly

3. Galarian Articuno

Psycho Cut + Fly

4. Rayquaza

Air Slash + Dragon Ascent

5. Moltres

Wing Attack + Fly

6. Zacian (Crowned Sword)

Air Slash + Play Rough

See the full ranked counter list for Zamazenta · 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.