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 3 to be safe — 2 if everyone is prepared

At level 40, a party of Tangrowth's top six counters needs 1.78 trainers (round up: 2), and a mixed lobby of ranks 13-24 needs 2.23 (round up: 3). The raid timer is 300 seconds and one prepared trainer alone would take 8:13. No level in this range makes it soloable with a prepared party. A duo works from level 30.

Tangrowth · Tier 5

grass

Weak to

flyingpoisonbugfireice

Boss CP: 38,355
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 Tangrowth 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(2.44)	3(2.78)	4(3.27)	12:48	6.0
Level 25	3(2.07)	3(2.30)	3(2.78)	10:36	6.0
Level 30	2(1.84)	2(1.97)	3(2.47)	9:04	6.0
Level 35	2(1.75)	2(1.88)	3(2.35)	8:38	5.9
Level 40	2(1.66)	2(1.78)	3(2.23)	8:13	5.9
Level 45	2(1.60)	2(1.72)	3(2.15)	7:56	5.8
Level 50	2(1.54)	2(1.66)	3(2.07)	7:39	5.7

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

Kyurem (White)1.66

A prepared party

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

2 trainers at level 40

Kyurem (White)1.66
Rayquaza1.71
Eternatus1.75
Blacephalon1.81
Kyurem (Black)1.89
Reshiram1.89

A mixed local group

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

3 trainers at level 40

Galarian Articuno2.15
Zamazenta (Crowned Shield)2.17
Toucannon2.18
Zacian (Crowned Sword)2.18
Nihilego2.24
Braviary2.26

The party these numbers assume

1. Kyurem (White)

Ice Fang + Ice Burn

2. Rayquaza

Air Slash + Dragon Ascent

3. Eternatus

Poison Jab + Dynamax Cannon

4. Blacephalon

Incinerate + Mind Blown

5. Kyurem (Black)

Dragon Tail + Freeze Shock

6. Reshiram

Fire Fang + Fusion Flare

See the full ranked counter list for Tangrowth · 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.