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 Steenee's top six counters needs 1.57 trainers (round up: 2), and a mixed lobby of ranks 13-24 needs 1.92 (round up: 2). The raid timer is 300 seconds and one prepared trainer alone would take 7:13. No level in this range makes it soloable with a prepared party. A duo works from level 25.

Steenee · Elite

grass

Weak to

flyingpoisonbugfireice

Boss CP: 13,731
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 Steenee 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	3(2.02)	3(2.16)	3(2.65)	9:58	5.7
Level 25	2(1.75)	2(1.89)	3(2.33)	8:43	5.3
Level 30	2(1.58)	2(1.71)	3(2.10)	7:52	4.8
Level 35	2(1.50)	2(1.63)	3(2.00)	7:29	4.4
Level 40	2(1.43)	2(1.57)	2(1.92)	7:13	4.3
Level 45	2(1.38)	2(1.51)	2(1.85)	6:58	4.1
Level 50	2(1.32)	2(1.46)	2(1.80)	6:43	3.9

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

Blacephalon1.43

A prepared party

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

2 trainers at level 40

Blacephalon1.43
Kyurem (White)1.51
Rayquaza1.55
Eternatus1.61
Kyurem (Black)1.64
Reshiram1.67

A mixed local group

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

2 trainers at level 40

Volcarona1.86
Chandelure1.87
Pheromosa1.87
Darmanitan (Standard)1.90
Heatran1.91
Naganadel1.93

The party these numbers assume

1. Blacephalon

Incinerate + Mind Blown

2. Kyurem (White)

Ice Fang + Ice Burn

3. Rayquaza

Air Slash + Dragon Ascent

4. Eternatus

Poison Jab + Dynamax Cannon

5. Kyurem (Black)

Dragon Tail + Freeze Shock

6. Reshiram

Fire Fang + Fusion Flare

See the full ranked counter list for Steenee · 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.