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 Dialga (Origin)'s top six counters needs 0.81 trainers (round up: 1), and a mixed lobby of ranks 13-24 needs 1.02 (round up: 2). The raid timer is 180 seconds and one prepared trainer alone would take 2:22. A prepared solo becomes possible at level 30. A duo works from level 20.

Dialga (Origin) · Tier 3

steeldragon

Weak to

fightingground

Boss CP: 26,491
Boss HP: 3,600
Raid timer: 180s
Party used: 6

Trainers needed, by attacker level

Scroll sideways for the mixed-lobby column.

Trainers needed to beat Dialga (Origin) 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(1.09)	2(1.23)	2(1.58)	3:37	6.0
Level 25	1(0.84)	2(1.04)	2(1.33)	3:02	5.9
Level 30	1(0.73)	1(0.91)	2(1.14)	2:40	5.6
Level 35	1(0.71)	1(0.85)	2(1.07)	2:29	5.3
Level 40	1(0.69)	1(0.81)	2(1.02)	2:22	4.9
Level 45	1(0.65)	1(0.77)	1(0.99)	2:15	4.6
Level 50	1(0.65)	1(0.75)	1(0.96)	2:11	4.5

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

Keldeo0.69

A prepared party

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

1 trainer at level 40

Keldeo0.69
Lucario0.78
Landorus (Therian)0.79
Terrakion0.81
Blaziken0.88
Urshifu (Single Strike)0.89

A mixed local group

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

2 trainers at level 40

Excadrill0.95
Marshadow1.00
Machamp1.01
Mewtwo1.02
Hisuian Decidueye1.02
Pheromosa1.01

The party these numbers assume

1. Keldeo

Low Kick + Secret Sword

2. Lucario

Force Palm + Aura Sphere

3. Landorus (Therian)

Mud Shot + Sandsear Storm

4. Terrakion

Double Kick + Sacred Sword

5. Blaziken

Counter + Aura Sphere

6. Urshifu (Single Strike)

Counter + Dynamic Punch

See the full ranked counter list for Dialga (Origin) · 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.