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 4.58 trainers (round up: 5), and a mixed lobby of ranks 13-24 needs 5.82 (round up: 6). The raid timer is 300 seconds and one prepared trainer alone would take 21:04. No level in this range makes it soloable with a prepared party.

Groudon · Elite

ground

Weak to

watergrassice

Boss CP: 62,829
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 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(6.72)	9(8.44)	9(8.76)	38:51	6.0
Level 25	6(5.23)	7(6.90)	8(7.67)	31:46	6.0
Level 30	4(3.96)	6(5.35)	7(6.64)	24:38	6.0
Level 35	4(3.79)	5(4.90)	7(6.12)	22:34	6.0
Level 40	4(3.59)	5(4.58)	6(5.82)	21:04	6.0
Level 45	4(3.47)	5(4.32)	6(5.55)	19:54	6.0
Level 50	4(3.34)	5(4.23)	6(5.15)	19:28	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)3.59

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)3.59
Kyurem (Black)4.09
Zarude4.55
Zamazenta (Crowned Shield)4.88
Necrozma (Dawn Wings)5.08
Shaymin (Sky)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

Golisopod5.52
Primarina5.32
Gyarados5.50
Inteleon5.54
Rillaboom5.90
Sceptile5.95

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)

Ice Fang + Behemoth Bash

5. Necrozma (Dawn Wings)

Psycho Cut + Moongeist Beam

6. Shaymin (Sky)

Magical Leaf + Grass Knot

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.