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 5 to be safe — 4 if everyone is prepared

At level 40, a party of Victini's top six counters needs 3.94 trainers (round up: 4), and a mixed lobby of ranks 13-24 needs 4.53 (round up: 5). The raid timer is 300 seconds and one prepared trainer alone would take 18:07. No level in this range makes it soloable with a prepared party.

Victini · Elite

psychicfire

Weak to

groundrockghostwaterdark

Boss CP: 47,729
Boss HP: 20,000
Raid timer: 300s
Party used: 6

Trainers needed, by attacker level

Scroll sideways for the mixed-lobby column.

Trainers needed to beat Victini 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	5(4.74)	6(5.77)	7(6.97)	26:32	6.0
Level 25	5(4.04)	6(5.08)	6(5.80)	23:22	6.0
Level 30	4(3.46)	5(4.41)	6(5.00)	20:19	5.9
Level 35	4(3.33)	5(4.10)	5(4.73)	18:52	5.8
Level 40	4(3.20)	4(3.94)	5(4.53)	18:07	5.8
Level 45	4(3.03)	4(3.75)	5(4.33)	17:17	5.8
Level 50	3(2.97)	4(3.66)	5(4.19)	16:52	5.8

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.

4 trainers at level 40

Necrozma (Dawn Wings)3.20

A prepared party

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

4 trainers at level 40

Necrozma (Dawn Wings)3.20
Landorus (Therian)3.85
Lunala4.07
Hydreigon4.11
Kyogre4.19
Eternatus4.19

A mixed local group

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

5 trainers at level 40

Dragapult4.38
Tyranitar4.51
Rhyperior4.42
Glimmora4.50
Giratina (Origin)4.49
Primarina4.51

The party these numbers assume

1. Necrozma (Dawn Wings)

Psycho Cut + Moongeist Beam

2. Landorus (Therian)

Mud Shot + Sandsear Storm

3. Lunala

Shadow Claw + Shadow Ball

4. Hydreigon

Bite + Brutal Swing

5. Kyogre

Waterfall + Origin Pulse

6. Eternatus

Poison Jab + Dynamax Cannon

See the full ranked counter list for Victini · 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.