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 1 to be safe — 1 if everyone is prepared

At level 40, a party of Riolu's top six counters needs 0.05 trainers (round up: 1), and a mixed lobby of ranks 13-24 needs 0.05 (round up: 1). The raid timer is 180 seconds and one prepared trainer alone would take 0:08. A prepared solo becomes possible at level 20. A duo works from level 20.

Riolu · Tier 1

fighting

Weak to

flyingpsychicfairy

Boss CP: 3,354
Boss HP: 600
Raid timer: 180s
Party used: 6

Trainers needed, by attacker level

Scroll sideways for the mixed-lobby column.

Trainers needed to beat Riolu at each attacker level
Attacker level	Six of the best counter	A prepared party	A mixed local group	Prepared solo time
Level 20	1(0.08)	1(0.07)	1(0.07)	0:13
Level 25	1(0.06)	1(0.06)	1(0.06)	0:11
Level 30	1(0.05)	1(0.05)	1(0.06)	0:10
Level 35	1(0.05)	1(0.05)	1(0.06)	0:09
Level 40	1(0.04)	1(0.05)	1(0.05)	0:08
Level 45	1(0.04)	1(0.04)	1(0.05)	0:08
Level 50	1(0.04)	1(0.04)	1(0.05)	0:08

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

Zacian (Crowned Sword)0.04

A prepared party

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

1 trainer at level 40

Zacian (Crowned Sword)0.04
Mewtwo0.04
Tapu Lele0.04
Galarian Articuno0.04
Toucannon0.05
Hoopa (Unbound)0.05

A mixed local group

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

1 trainer at level 40

Espeon0.05
Deoxys0.05
Deoxys (Attack)0.05
Necrozma (Dusk Mane)0.05
Rayquaza0.05
Necrozma0.05

The party these numbers assume

1. Zacian (Crowned Sword)

Metal Claw + Play Rough

2. Mewtwo

Psycho Cut + Psystrike

3. Tapu Lele

Confusion + Nature's Madness

4. Galarian Articuno

Confusion + Fly

5. Toucannon

Peck + Beak Blast

6. Hoopa (Unbound)

Confusion + Psychic

See the full ranked counter list for Riolu · 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.