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 4 to be safe — 3 if everyone is prepared

At level 40, a party of Mega Lucario Z's top six counters needs 2.64 trainers (round up: 3), and a mixed lobby of ranks 13-24 needs 3.22 (round up: 4). The raid timer is 300 seconds and one prepared trainer alone would take 12:16. No level in this range makes it soloable with a prepared party.

Mega Lucario Z · Mega Legendary

fightingsteel

Weak to

fightinggroundfire

Boss CP: 74,425
Boss HP: 22,500
Raid timer: 300s
Party used: 6

Trainers needed, by attacker level

Scroll sideways for the mixed-lobby column.

Trainers needed to beat Mega Lucario Z 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	4(3.76)	5(4.43)	6(5.38)	20:36	6.0
Level 25	3(2.76)	4(3.58)	5(4.30)	16:39	6.0
Level 30	3(2.51)	4(3.06)	4(3.62)	14:14	6.0
Level 35	3(2.30)	3(2.88)	4(3.39)	13:22	6.0
Level 40	3(2.21)	3(2.64)	4(3.22)	12:16	6.0
Level 45	3(2.14)	3(2.53)	4(3.06)	11:46	6.0
Level 50	3(2.08)	3(2.41)	3(2.94)	11:12	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.

3 trainers at level 40

Keldeo2.21

A prepared party

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

3 trainers at level 40

Keldeo2.21
Reshiram2.61
Blacephalon2.66
Landorus (Therian)2.75
Terrakion2.85
Blaziken2.76

A mixed local group

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

4 trainers at level 40

Ho-Oh3.11
Volcarona3.12
Gallade3.16
Garchomp3.21
Emboar3.20
Marshadow3.24

The party these numbers assume

1. Keldeo

Low Kick + Secret Sword

2. Reshiram

Fire Fang + Fusion Flare

3. Blacephalon

Incinerate + Mind Blown

4. Landorus (Therian)

Mud Shot + Sandsear Storm

5. Terrakion

Double Kick + Sacred Sword

6. Blaziken

Counter + Aura Sphere

See the full ranked counter list for Mega Lucario Z · 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.