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 6 to be safe — 5 if everyone is prepared

At level 40, a party of Dialga (Origin)'s top six counters needs 4.29 trainers (round up: 5), and a mixed lobby of ranks 13-24 needs 5.64 (round up: 6). The raid timer is 300 seconds and one prepared trainer alone would take 20:17. No level in this range makes it soloable with a prepared party.

Dialga (Origin) · Shadow Tier 5

steeldragon

Weak to

fightingground

Boss CP: 54,074
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 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	6(5.87)	8(7.14)	9(8.66)	33:43	6.0
Level 25	6(5.34)	7(6.11)	8(7.32)	28:53	6.0
Level 30	5(4.70)	6(5.29)	7(6.41)	25:00	6.0
Level 35	5(4.03)	5(4.68)	7(6.08)	22:07	6.0
Level 40	4(3.37)	5(4.29)	6(5.64)	20:17	6.0
Level 45	4(3.29)	5(4.09)	6(5.36)	19:19	6.0
Level 50	4(3.17)	4(3.94)	6(5.17)	18:37	6.0

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.

4 trainers at level 40

Keldeo3.37

A prepared party

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

5 trainers at level 40

Keldeo3.37
Lucario4.12
Terrakion4.13
Groudon4.55
Kartana4.78
Urshifu (Rapid Strike)4.82

A mixed local group

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

6 trainers at level 40

Necrozma (Dawn Wings)5.32
Cobalion5.35
Virizion5.41
Landorus (Incarnate)5.46
Mewtwo5.61
Buzzwole5.59

The party these numbers assume

1. Keldeo

Low Kick + Secret Sword

2. Lucario

Force Palm + Aura Sphere

3. Terrakion

Double Kick + Sacred Sword

4. Groudon

Mud Shot + Precipice Blades

5. Kartana

Fury Cutter + Sacred Sword

6. Urshifu (Rapid 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.