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 3.53 trainers (round up: 4), and a mixed lobby of ranks 13-24 needs 4.37 (round up: 5). The raid timer is 300 seconds and one prepared trainer alone would take 16:42. No level in this range makes it soloable with a prepared party.

Corviknight · Shadow Tier 5

flyingsteel

Weak to

fireelectric

Boss CP: 31,365
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 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	6(5.28)	6(5.21)	7(6.78)	24:35	6.0
Level 25	5(4.15)	5(4.41)	6(5.73)	20:50	6.0
Level 30	4(3.75)	4(3.91)	5(4.90)	18:28	6.0
Level 35	4(3.61)	4(3.70)	5(4.58)	17:29	6.0
Level 40	4(3.44)	4(3.53)	5(4.37)	16:42	6.0
Level 45	4(3.25)	4(3.41)	5(4.23)	16:06	6.0
Level 50	4(3.16)	4(3.29)	5(4.06)	15:31	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

Regieleki3.44

A prepared party

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

4 trainers at level 40

Regieleki3.44
Thundurus (Therian)3.53
Reshiram3.52
Xurkitree3.54
Zeraora3.57
Zekrom3.60

A mixed local group

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

5 trainers at level 40

Kyurem (White)4.25
Chandelure4.30
Darmanitan (Standard)4.28
Magnezone4.33
Moltres4.36
Entei4.34

The party these numbers assume

1. Regieleki

Lock-On + Thunder Cage

2. Thundurus (Therian)

Volt Switch + Wildbolt Storm

3. Reshiram

Fire Fang + Fusion Flare

4. Xurkitree

Thunder Shock + Discharge

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.