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 — 5 if everyone is prepared

At level 40, a party of Groudon's top six counters needs 4.67 trainers (round up: 5), and a mixed lobby of ranks 13-24 needs 5.99 (round up: 6). The raid timer is 300 seconds and one prepared trainer alone would take 22:04. No level in this range makes it soloable with a prepared party.

Groudon · Shadow Tier 5

ground

Weak to

watergrassice

Boss CP: 54,411
Boss HP: 15,000
Raid timer: 300s
Party used: 6

Trainers needed, by attacker level

Scroll sideways for the mixed-lobby column.

Trainers needed to beat Groudon 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(6.84)	9(8.25)	10(9.64)	38:58	6.0
Level 25	6(5.39)	7(6.89)	8(7.93)	32:34	6.0
Level 30	5(4.23)	6(5.44)	7(6.85)	25:41	6.0
Level 35	4(3.94)	6(5.06)	7(6.29)	23:54	6.0
Level 40	4(3.80)	5(4.67)	6(5.99)	22:04	6.0
Level 45	4(3.67)	5(4.53)	6(5.78)	21:24	6.0
Level 50	4(3.53)	5(4.42)	6(5.56)	20:52	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

Kyurem (White)3.80

A prepared party

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

5 trainers at level 40

Kyurem (White)3.80
Kyurem (Black)4.28
Zarude4.61
Zamazenta (Crowned Shield)4.87
Shaymin (Sky)5.18
Necrozma (Dawn Wings)5.28

A mixed local group

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

6 trainers at level 40

Gyarados5.61
Kyurem5.63
Golisopod5.68
Sceptile5.91
Regigigas5.82
Swampert5.77

The party these numbers assume

1. Kyurem (White)

Ice Fang + Ice Burn

2. Kyurem (Black)

Dragon Tail + Freeze Shock

3. Zarude

Vine Whip + Power Whip

4. Zamazenta (Crowned Shield)

Metal Claw + Behemoth Bash

5. Shaymin (Sky)

Magical Leaf + Grass Knot

6. Necrozma (Dawn Wings)

Psycho Cut + Moongeist Beam

See the full ranked counter list for Groudon · 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.