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 Pachirisu's top six counters needs 3.32 trainers (round up: 4), and a mixed lobby of ranks 13-24 needs 4.17 (round up: 5). The raid timer is 300 seconds and one prepared trainer alone would take 15:16. No level in this range makes it soloable with a prepared party.

Pachirisu · Elite

electric

Weak to

ground

Boss CP: 21,079
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 Pachirisu 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(4.11)	5(4.56)	6(5.79)	20:58	5.4
Level 25	4(3.45)	5(4.04)	6(5.05)	18:34	5.0
Level 30	4(3.21)	4(3.65)	5(4.50)	16:46	4.3
Level 35	4(3.09)	4(3.50)	5(4.33)	16:06	4.2
Level 40	3(2.85)	4(3.32)	5(4.17)	15:16	3.9
Level 45	3(2.78)	4(3.21)	5(4.03)	14:45	3.6
Level 50	3(2.71)	4(3.13)	4(3.93)	14:23	3.3

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

Landorus (Therian)2.85

A prepared party

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

4 trainers at level 40

Landorus (Therian)2.85
Groudon3.27
Necrozma (Dawn Wings)3.38
Eternatus3.38
Excadrill3.46
Mamoswine3.57

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 (White)3.94
Golurk3.99
Rhydon3.99
Keldeo4.04
Blacephalon4.11
Mudsdale4.19

The party these numbers assume

1. Landorus (Therian)

Mud Shot + Sandsear Storm

2. Groudon

Mud Shot + Precipice Blades

3. Necrozma (Dawn Wings)

Psycho Cut + Moongeist Beam

4. Eternatus

Poison Jab + Dynamax Cannon

5. Excadrill

Mud-Slap + Scorching Sands

6. Mamoswine

Mud-Slap + High Horsepower

See the full ranked counter list for Pachirisu · 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.