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 — 1 if everyone is prepared

At level 40, a party of Bagon's top six counters needs 0.88 trainers (round up: 1), and a mixed lobby of ranks 13-24 needs 1.16 (round up: 2). The raid timer is 300 seconds and one prepared trainer alone would take 4:04. A prepared solo becomes possible at level 30. A duo works from level 20.

Bagon · Tier 5

dragon

Weak to

icedragonfairy

Boss CP: 18,964
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 Bagon 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(1.02)	2(1.24)	2(1.62)	5:42	5.8
Level 25	1(0.90)	2(1.08)	2(1.41)	4:59	5.5
Level 30	1(0.82)	1(0.97)	2(1.27)	4:29	4.9
Level 35	1(0.77)	1(0.92)	2(1.21)	4:15	4.5
Level 40	1(0.74)	1(0.88)	2(1.16)	4:04	4.1
Level 45	1(0.74)	1(0.86)	2(1.13)	3:57	3.8
Level 50	1(0.71)	1(0.83)	2(1.08)	3:49	3.3

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

Eternatus0.74

A prepared party

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

1 trainer at level 40

Eternatus0.74
Kyurem (Black)0.79
Kyurem (White)0.88
Palkia (Origin)0.94
Baxcalibur0.96
Dialga (Origin)0.98

A mixed local group

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

2 trainers at level 40

Regidrago1.10
Zacian (Crowned Sword)1.11
Dragonite1.12
Reshiram1.13
Dialga1.14
Enamorus (Incarnate)1.16

The party these numbers assume

1. Eternatus

Dragon Tail + Dynamax Cannon

2. Kyurem (Black)

Dragon Tail + Freeze Shock

3. Kyurem (White)

Ice Fang + Ice Burn

4. Palkia (Origin)

Dragon Tail + Spacial Rend

5. Baxcalibur

Ice Fang + Glaive Rush

6. Dialga (Origin)

Dragon Breath + Roar of Time

See the full ranked counter list for Bagon · 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.