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 Corviknight's top six counters needs 3.35 trainers (round up: 4), and a mixed lobby of ranks 13-24 needs 4.15 (round up: 5). The raid timer is 300 seconds and one prepared trainer alone would take 15:26. No level in this range makes it soloable with a prepared party.

Corviknight · Elite

flyingsteel

Weak to

fireelectric

Boss CP: 36,217
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 Corviknight 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(4.97)	6(5.07)	7(6.39)	23:21	6.0
Level 25	5(4.15)	5(4.23)	6(5.39)	19:28	6.0
Level 30	4(3.78)	4(3.76)	5(4.63)	17:19	6.0
Level 35	4(3.44)	4(3.52)	5(4.33)	16:12	6.0
Level 40	4(3.24)	4(3.35)	5(4.15)	15:26	6.0
Level 45	4(3.18)	4(3.22)	4(4.00)	14:48	6.0
Level 50	4(3.13)	4(3.09)	4(3.82)	14:12	6.0

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.

4 trainers at level 40

Reshiram3.24

A prepared party

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

4 trainers at level 40

Reshiram3.24
Xurkitree3.33
Regieleki3.32
Thundurus (Therian)3.39
Zeraora3.39
Zekrom3.46

A mixed local group

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

5 trainers at level 40

Raikou3.98
Darmanitan (Standard)4.08
Magnezone4.12
Incineroar4.13
Entei4.11
Chandelure4.16

The party these numbers assume

1. Reshiram

Fire Fang + Fusion Flare

2. Xurkitree

Thunder Shock + Discharge

3. Regieleki

Thunder Shock + Thunder Cage

4. Thundurus (Therian)

Volt Switch + Wildbolt Storm

5. Zeraora

Volt Switch + Plasma Fists

6. Zekrom

Charge Beam + Fusion Bolt

See the full ranked counter list for Corviknight · 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.