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 Mewtwo's top six counters needs 3.58 trainers (round up: 4), and a mixed lobby of ranks 13-24 needs 4.18 (round up: 5). The raid timer is 300 seconds and one prepared trainer alone would take 16:27. No level in this range makes it soloable with a prepared party.

Mewtwo · Elite

psychic

Weak to

bugghostdark

Boss CP: 62,525
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 Mewtwo 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(4.02)	6(5.60)	7(6.84)	25:47	6.0
Level 25	4(3.67)	5(4.67)	6(5.60)	21:30	6.0
Level 30	4(3.12)	5(4.00)	5(4.80)	18:26	6.0
Level 35	4(3.05)	4(3.70)	5(4.41)	17:02	6.0
Level 40	3(2.89)	4(3.58)	5(4.18)	16:27	6.0
Level 45	3(2.63)	4(3.44)	5(4.01)	15:50	5.9
Level 50	3(2.55)	4(3.35)	4(3.84)	15:26	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.

3 trainers at level 40

Necrozma (Dawn Wings)2.89

A prepared party

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

4 trainers at level 40

Necrozma (Dawn Wings)2.89
Lunala3.51
Eternatus3.72
Darkrai3.76
Tyranitar3.78
Hydreigon3.80

A mixed local group

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

5 trainers at level 40

Kyurem (Black)3.95
Hoopa (Unbound)4.10
Hoopa4.13
Necrozma (Dusk Mane)4.08
Volcarona4.12
Vikavolt4.14

The party these numbers assume

1. Necrozma (Dawn Wings)

Shadow Claw + Moongeist Beam

2. Lunala

Shadow Claw + Shadow Ball

3. Eternatus

Dragon Tail + Dynamax Cannon

4. Darkrai

Snarl + Foul Play

5. Tyranitar

Bite + Brutal Swing

6. Hydreigon

Bite + Brutal Swing

See the full ranked counter list for Mewtwo · 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.