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 Regidrago's top six counters needs 1.00 trainers (round up: 2), and a mixed lobby of ranks 13-24 needs 1.30 (round up: 2). The raid timer is 300 seconds and one prepared trainer alone would take 4:37. A prepared solo becomes possible at level 45. A duo works from level 20.

Regidrago · Tier 5

dragon

Weak to

icedragonfairy

Boss CP: 28,624
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 Regidrago 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(1.20)	2(1.54)	3(2.02)	7:04	6.0
Level 25	2(1.08)	2(1.26)	2(1.61)	5:47	6.0
Level 30	1(0.92)	2(1.11)	2(1.42)	5:06	5.9
Level 35	1(0.89)	2(1.06)	2(1.37)	4:53	5.8
Level 40	1(0.85)	2(1.00)	2(1.30)	4:37	5.8
Level 45	1(0.80)	1(0.97)	2(1.26)	4:29	5.7
Level 50	1(0.76)	1(0.93)	2(1.21)	4:16	5.6

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

Eternatus0.85

A prepared party

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

2 trainers at level 40

Eternatus0.85
Kyurem (Black)0.89
Kyurem (White)0.97
Palkia (Origin)1.10
Dialga (Origin)1.10
Baxcalibur1.10

A mixed local group

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

2 trainers at level 40

Dialga1.26
Palkia1.26
Salamence1.27
Zamazenta (Crowned Shield)1.27
Dragonite1.28
Enamorus (Incarnate)1.29

The party these numbers assume

1. Eternatus

Dragon Tail + Dynamax Cannon

2. Kyurem (Black)

Dragon Tail + Freeze Shock

3. Kyurem (White)

Dragon Breath + Ice Burn

4. Palkia (Origin)

Dragon Tail + Spacial Rend

5. Dialga (Origin)

Dragon Breath + Roar of Time

6. Baxcalibur

Ice Fang + Glaive Rush

See the full ranked counter list for Regidrago · 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.