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 Onix's top six counters needs 1.58 trainers (round up: 2), and a mixed lobby of ranks 13-24 needs 1.83 (round up: 2). The raid timer is 300 seconds and one prepared trainer alone would take 7:17. No level in this range makes it soloable with a prepared party. A duo works from level 25.

Onix · Tier 5

rockground

Weak to

watergrassfightinggroundsteelice

Boss CP: 19,248
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 Onix 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(1.97)	3(2.16)	3(2.51)	9:56	5.4
Level 25	2(1.72)	2(1.91)	3(2.21)	8:47	4.9
Level 30	2(1.56)	2(1.74)	3(2.00)	8:00	4.5
Level 35	2(1.49)	2(1.65)	2(1.91)	7:36	4.2
Level 40	2(1.43)	2(1.58)	2(1.83)	7:17	3.9
Level 45	2(1.38)	2(1.54)	2(1.77)	7:05	3.8
Level 50	2(1.33)	2(1.48)	2(1.71)	6:49	3.6

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.

2 trainers at level 40

Kartana1.43

A prepared party

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

2 trainers at level 40

Kartana1.43
Inteleon1.57
Kyogre1.57
Shaymin (Sky)1.57
Zarude1.66
Zacian (Crowned Sword)1.68

A mixed local group

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

2 trainers at level 40

Zamazenta (Crowned Shield)1.77
Primarina1.77
Necrozma (Dusk Mane)1.80
Tapu Bulu1.81
Breloom1.82
Chesnaught1.83

The party these numbers assume

1. Kartana

Razor Leaf + Leaf Blade

2. Inteleon

Water Gun + Hydro Cannon

3. Kyogre

Waterfall + Origin Pulse

4. Shaymin (Sky)

Magical Leaf + Grass Knot

5. Zarude

Vine Whip + Power Whip

6. Zacian (Crowned Sword)

Metal Claw + Behemoth Blade

See the full ranked counter list for Onix · 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.