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 Piplup's top six counters needs 1.08 trainers (round up: 2), and a mixed lobby of ranks 13-24 needs 1.36 (round up: 2). The raid timer is 300 seconds and one prepared trainer alone would take 4:58. No level in this range makes it soloable with a prepared party. A duo works from level 20.

Piplup · Tier 5

water

Weak to

grasselectric

Boss CP: 16,824
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 Piplup 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(1.46)	2(1.51)	2(1.90)	6:57	5.9
Level 25	2(1.24)	2(1.33)	2(1.66)	6:06	5.8
Level 30	2(1.09)	2(1.18)	2(1.49)	5:26	5.4
Level 35	2(1.03)	2(1.13)	2(1.42)	5:11	5.3
Level 40	1(1.00)	2(1.08)	2(1.36)	4:58	4.9
Level 45	1(0.94)	2(1.04)	2(1.31)	4:48	4.6
Level 50	1(0.90)	2(1.00)	2(1.27)	4:37	4.2

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.

1 trainer at level 40

Regieleki1.00

A prepared party

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

2 trainers at level 40

Regieleki1.00
Thundurus (Therian)1.06
Kartana1.08
Zeraora1.08
Xurkitree1.11
Zekrom1.16

A mixed local group

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

2 trainers at level 40

Raikou1.30
Meowscarada1.31
Roserade1.32
Necrozma (Dawn Wings)1.33
Magnezone1.36
Tapu Bulu1.37

The party these numbers assume

1. Regieleki

Lock-On + Thunder Cage

2. Thundurus (Therian)

Volt Switch + Wildbolt Storm

3. Kartana

Razor Leaf + Leaf Blade

4. Zeraora

Volt Switch + Plasma Fists

5. Xurkitree

Thunder Shock + Discharge

6. Zekrom

Charge Beam + Fusion Bolt

See the full ranked counter list for Piplup · 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.