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 6 to be safe — 4 if everyone is prepared

At level 40, a party of Raikou's top six counters needs 3.87 trainers (round up: 4), and a mixed lobby of ranks 13-24 needs 5.01 (round up: 6). The raid timer is 300 seconds and one prepared trainer alone would take 17:49. No level in this range makes it soloable with a prepared party.

Raikou · Elite

electric

Weak to

ground

Boss CP: 52,464
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 Raikou 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	6(5.23)	6(5.69)	8(7.39)	26:11	6.0
Level 25	5(4.53)	6(5.01)	7(6.53)	23:04	5.9
Level 30	4(3.83)	5(4.35)	6(5.63)	20:00	5.8
Level 35	4(3.65)	5(4.11)	6(5.25)	18:54	5.7
Level 40	4(3.44)	4(3.87)	6(5.01)	17:49	5.7
Level 45	4(3.34)	4(3.73)	5(4.85)	17:10	5.6
Level 50	4(3.25)	4(3.64)	5(4.69)	16:44	5.5

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

Landorus (Therian)3.44

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)3.44
Groudon3.64
Eternatus3.90
Garchomp3.98
Landorus (Incarnate)4.12
Mamoswine4.14

A mixed local group

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

6 trainers at level 40

Krookodile4.68
Golurk4.76
Hippowdon4.92
Rhydon4.89
Torterra5.02
Mudsdale5.00

The party these numbers assume

1. Landorus (Therian)

Mud Shot + Sandsear Storm

2. Groudon

Mud Shot + Precipice Blades

3. Eternatus

Poison Jab + Dynamax Cannon

4. Garchomp

Mud Shot + Earth Power

5. Landorus (Incarnate)

Mud Shot + Earth Power

6. Mamoswine

Mud-Slap + High Horsepower

See the full ranked counter list for Raikou · 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.