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 Mega Latios's top six counters needs 3.64 trainers (round up: 4), and a mixed lobby of ranks 13-24 needs 4.83 (round up: 5). The raid timer is 300 seconds and one prepared trainer alone would take 16:44. No level in this range makes it soloable with a prepared party.

Mega Latios · Super Mega

dragonpsychic

Weak to

bugghosticedragondarkfairy

Boss CP: 88,543
Boss HP: 25,000
Raid timer: 300s
Party used: 6

Trainers needed, by attacker level

Scroll sideways for the mixed-lobby column.

Trainers needed to beat Mega Latios 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(5.52)	7(6.35)	8(7.91)	29:14	6.0
Level 25	4(3.91)	5(4.87)	7(6.42)	22:24	6.0
Level 30	4(3.36)	5(4.11)	6(5.42)	18:54	6.0
Level 35	4(3.21)	4(3.82)	6(5.13)	17:36	6.0
Level 40	4(3.03)	4(3.64)	5(4.83)	16:44	6.0
Level 45	3(2.96)	4(3.50)	5(4.61)	16:05	6.0
Level 50	3(2.80)	4(3.40)	5(4.47)	15:38	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

Eternatus3.03

A prepared party

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

4 trainers at level 40

Eternatus3.03
Kyurem (Black)3.29
Necrozma (Dawn Wings)3.64
Kyurem (White)3.67
Baxcalibur4.06
Rayquaza4.12

A mixed local group

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

5 trainers at level 40

Lunala4.49
Regidrago4.63
Hydreigon4.70
Salamence4.76
Giratina (Origin)4.81
Kyurem4.88

The party these numbers assume

1. Eternatus

Dragon Tail + Dynamax Cannon

2. Kyurem (Black)

Dragon Tail + Freeze Shock

3. Necrozma (Dawn Wings)

Shadow Claw + Moongeist Beam

4. Kyurem (White)

Dragon Breath + Ice Burn

5. Baxcalibur

Dragon Breath + Glaive Rush

6. Rayquaza

Dragon Tail + Breaking Swipe

See the full ranked counter list for Mega Latios · 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.