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 Alolan Sandshrew's top six counters needs 0.81 trainers (round up: 1), and a mixed lobby of ranks 13-24 needs 1.01 (round up: 2). The raid timer is 300 seconds and one prepared trainer alone would take 3:44. A prepared solo becomes possible at level 25. A duo works from level 20.

Alolan Sandshrew · Tier 5

icesteel

Weak to

fightingfireground

Boss CP: 20,575
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 Alolan Sandshrew 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(1.07)	2(1.15)	2(1.43)	5:17	5.8
Level 25	1(0.94)	1(0.99)	2(1.25)	4:33	5.4
Level 30	1(0.80)	1(0.89)	2(1.10)	4:05	5.0
Level 35	1(0.77)	1(0.85)	2(1.06)	3:53	4.8
Level 40	1(0.73)	1(0.81)	2(1.01)	3:44	4.5
Level 45	1(0.70)	1(0.78)	1(0.97)	3:36	4.3
Level 50	1(0.67)	1(0.76)	1(0.94)	3:29	4.0

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.

1 trainer at level 40

Blacephalon0.73

A prepared party

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

1 trainer at level 40

Blacephalon0.73
Keldeo0.74
Lucario0.82
Reshiram0.83
Terrakion0.86
Blaziken0.87

A mixed local group

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

2 trainers at level 40

Urshifu (Single Strike)0.98
Conkeldurr0.98
Pheromosa1.00
Ho-Oh1.00
Emboar1.00
Delphox1.00

The party these numbers assume

1. Blacephalon

Incinerate + Mind Blown

2. Keldeo

Low Kick + Secret Sword

3. Lucario

Force Palm + Aura Sphere

4. Reshiram

Fire Fang + Fusion Flare

5. Terrakion

Double Kick + Sacred Sword

6. Blaziken

Counter + Aura Sphere

See the full ranked counter list for Alolan Sandshrew · 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.