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 Corviknight's top six counters needs 1.38 trainers (round up: 2), and a mixed lobby of ranks 13-24 needs 1.70 (round up: 2). The raid timer is 180 seconds and one prepared trainer alone would take 4:03. No level in this range makes it soloable with a prepared party. A duo works from level 25.

Corviknight · Shadow Tier 3

flyingsteel

Weak to

fireelectric

Boss CP: 16,197
Boss HP: 4,000
Raid timer: 180s
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	2(1.98)	3(2.00)	3(2.50)	5:52	6.0
Level 25	2(1.68)	2(1.70)	3(2.12)	4:59	5.9
Level 30	2(1.50)	2(1.51)	2(1.87)	4:26	5.5
Level 35	2(1.46)	2(1.45)	2(1.79)	4:14	5.3
Level 40	2(1.36)	2(1.38)	2(1.70)	4:03	5.0
Level 45	2(1.33)	2(1.34)	2(1.63)	3:56	4.9
Level 50	2(1.31)	2(1.29)	2(1.56)	3:46	4.7

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

Thundurus (Therian)1.36

A prepared party

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

2 trainers at level 40

Thundurus (Therian)1.36
Reshiram1.34
Regieleki1.35
Zeraora1.38
Xurkitree1.42
Zekrom1.44

A mixed local group

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

2 trainers at level 40

Raikou1.67
Blaziken1.66
Moltres1.68
Magnezone1.68
Darmanitan (Standard)1.68
Incineroar1.71

The party these numbers assume

1. Thundurus (Therian)

Volt Switch + Wildbolt Storm

2. Reshiram

Fire Fang + Fusion Flare

3. Regieleki

Lock-On + Thunder Cage

4. Zeraora

Volt Switch + Plasma Fists

5. Xurkitree

Thunder Shock + Discharge

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.