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 7 to be safe — 5 if everyone is prepared

At level 40, a party of Arceus (Electric)'s top six counters needs 4.89 trainers (round up: 5), and a mixed lobby of ranks 13-24 needs 6.10 (round up: 7). The raid timer is 300 seconds and one prepared trainer alone would take 22:31. No level in this range makes it soloable with a prepared party.

Arceus (Electric) · Elite

electric

Weak to

ground

Boss CP: 56,910
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 Arceus (Electric) 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	9(8.84)	9(8.56)	11(10.10)	39:24	6.0
Level 25	7(6.09)	7(6.36)	8(7.99)	29:17	6.0
Level 30	5(4.95)	6(5.39)	7(6.82)	24:47	6.0
Level 35	5(4.67)	6(5.12)	7(6.40)	23:33	6.0
Level 40	5(4.54)	5(4.89)	7(6.10)	22:31	6.0
Level 45	5(4.41)	5(4.74)	6(5.87)	21:49	6.0
Level 50	5(4.25)	5(4.60)	6(5.71)	21:11	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.

5 trainers at level 40

Landorus (Therian)4.54

A prepared party

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

5 trainers at level 40

Landorus (Therian)4.54
Groudon4.68
Necrozma (Dawn Wings)4.82
Excadrill5.09
Eternatus5.11
Garchomp5.13

A mixed local group

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

7 trainers at level 40

Krookodile5.69
Kyurem (White)5.68
Baxcalibur5.98
Dialga (Origin)6.04
Golurk6.04
Mewtwo6.07

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. Excadrill

Mud-Slap + Scorching Sands

5. Eternatus

Poison Jab + Dynamax Cannon

6. Garchomp

Mud Shot + Earth Power

See the full ranked counter list for Arceus (Electric) · 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.