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 2 to be safe — 2 if everyone is prepared

At level 40, a party of Wailmer's top six counters needs 1.31 trainers (round up: 2), and a mixed lobby of ranks 13-24 needs 1.63 (round up: 2). The raid timer is 300 seconds and one prepared trainer alone would take 6:01. No level in this range makes it soloable with a prepared party. A duo works from level 20.

Wailmer · Elite

water

Weak to

grasselectric

Boss CP: 19,454
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 Wailmer 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	2(1.86)	2(1.88)	3(2.28)	8:40	6.0
Level 25	2(1.54)	2(1.61)	2(1.99)	7:24	6.0
Level 30	2(1.37)	2(1.44)	2(1.78)	6:38	5.9
Level 35	2(1.29)	2(1.36)	2(1.70)	6:16	5.8
Level 40	2(1.21)	2(1.31)	2(1.63)	6:01	5.7
Level 45	2(1.17)	2(1.26)	2(1.57)	5:47	5.6
Level 50	2(1.15)	2(1.21)	2(1.52)	5:35	5.6

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.

2 trainers at level 40

Regieleki1.21

A prepared party

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

2 trainers at level 40

Regieleki1.21
Kartana1.30
Thundurus (Therian)1.30
Zeraora1.31
Xurkitree1.33
Zekrom1.39

A mixed local group

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

2 trainers at level 40

Roserade1.58
Kyurem (Black)1.58
Meowscarada1.59
Necrozma (Dawn Wings)1.61
Magnezone1.62
Decidueye1.63

The party these numbers assume

1. Regieleki

Lock-On + Thunder Cage

2. Kartana

Razor Leaf + Leaf Blade

3. Thundurus (Therian)

Volt Switch + Wildbolt Storm

4. Zeraora

Volt Switch + Plasma Fists

5. Xurkitree

Thunder Shock + Discharge

6. Zekrom

Charge Beam + Fusion Bolt

See the full ranked counter list for Wailmer · 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.