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 13 to be safe — 8 if everyone is prepared

At level 40, a party of Shuckle's top six counters needs 7.67 trainers (round up: 8), and a mixed lobby of ranks 13-24 needs 12.70 (round up: 13). The raid timer is 300 seconds and one prepared trainer alone would take 36:13. No level in this range makes it soloable with a prepared party.

Shuckle · Shadow Tier 5

bugrock

Weak to

rocksteelwater

Boss CP: 7,945
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 Shuckle 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	7(6.51)	10(9.32)	13(12.71)	44:00	2.4
Level 25	7(6.04)	9(8.89)	13(12.70)	42:01	1.7
Level 30	6(5.73)	9(8.14)	13(12.70)	38:26	1.6
Level 35	6(5.53)	8(7.97)	13(12.70)	37:40	1.4
Level 40	5(4.70)	8(7.67)	13(12.70)	36:13	1.2
Level 45	5(4.64)	8(7.56)	13(12.55)	35:42	1.1
Level 50	5(4.51)	8(7.42)	13(12.49)	35:04	1.0

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.

5 trainers at level 40

Zamazenta (Crowned Shield)4.70

A prepared party

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

8 trainers at level 40

Zamazenta (Crowned Shield)4.70
Necrozma (Dusk Mane)4.75
Zacian (Crowned Sword)4.84
Vaporeon9.97
Zekrom10.76
Latias10.98

A mixed local group

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

13 trainers at level 40

Spidops12.70
Doublade12.70
Lickilicky12.70
Meganium12.70
Haunter12.70
Electabuzz12.70

The party these numbers assume

1. Zamazenta (Crowned Shield)

Metal Claw + Behemoth Bash

2. Necrozma (Dusk Mane)

Metal Claw + Sunsteel Strike

3. Zacian (Crowned Sword)

Metal Claw + Behemoth Blade

4. Vaporeon

Water Gun + Aqua Tail

5. Zekrom

Dragon Breath + Outrage

6. Latias

Dragon Breath + Mist Ball

See the full ranked counter list for Shuckle · 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.