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 Mega Aerodactyl's top six counters needs 1.14 trainers (round up: 2), and a mixed lobby of ranks 13-24 needs 1.53 (round up: 2). The raid timer is 300 seconds and one prepared trainer alone would take 5:17. No level in this range makes it soloable with a prepared party. A duo works from level 20.

Mega Aerodactyl · Mega

rockflying

Weak to

rocksteelwaterelectricice

Boss CP: 43,686
Boss HP: 9,000
Raid timer: 300s
Party used: 6

Trainers needed, by attacker level

Scroll sideways for the mixed-lobby column.

Trainers needed to beat Mega Aerodactyl 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(1.31)	2(1.75)	3(2.35)	8:09	6.0
Level 25	2(1.18)	2(1.44)	2(1.92)	6:43	6.0
Level 30	2(1.05)	2(1.25)	2(1.68)	5:48	5.9
Level 35	2(1.02)	2(1.19)	2(1.59)	5:31	5.9
Level 40	1(0.99)	2(1.14)	2(1.53)	5:17	5.8
Level 45	1(0.92)	2(1.08)	2(1.47)	5:02	5.7
Level 50	1(0.89)	2(1.05)	2(1.42)	4:54	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

Zamazenta (Crowned Shield)0.99

A prepared party

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

2 trainers at level 40

Zamazenta (Crowned Shield)0.99
Zacian (Crowned Sword)1.01
Necrozma (Dusk Mane)1.02
Kyurem (White)1.18
Kyurem (Black)1.28
Zeraora1.35

A mixed local group

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

2 trainers at level 40

Kyogre1.48
Quaquaval1.49
Dialga1.52
Melmetal1.52
Inteleon1.49
Raikou1.54

The party these numbers assume

1. Zamazenta (Crowned Shield)

Metal Claw + Behemoth Bash

2. Zacian (Crowned Sword)

Metal Claw + Behemoth Blade

3. Necrozma (Dusk Mane)

Metal Claw + Sunsteel Strike

4. Kyurem (White)

Ice Fang + Ice Burn

5. Kyurem (Black)

Dragon Tail + Freeze Shock

6. Zeraora

Volt Switch + Plasma Fists

See the full ranked counter list for Mega Aerodactyl · 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.