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 3 to be safe — 2 if everyone is prepared

At level 40, a party of Giratina (Altered)'s top six counters needs 1.96 trainers (round up: 2), and a mixed lobby of ranks 13-24 needs 2.54 (round up: 3). The raid timer is 300 seconds and one prepared trainer alone would take 9:01. No level in this range makes it soloable with a prepared party. A duo works from level 40.

Giratina (Altered) · Tier 5

ghostdragon

Weak to

ghosticedragondarkfairy

Boss CP: 38,326
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 Giratina (Altered) 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	3(2.36)	3(2.83)	4(3.64)	13:03	6.0
Level 25	3(2.07)	3(2.45)	4(3.11)	11:15	6.0
Level 30	2(1.78)	3(2.17)	3(2.79)	10:00	6.0
Level 35	2(1.75)	3(2.06)	3(2.65)	9:28	6.0
Level 40	2(1.65)	2(1.96)	3(2.54)	9:01	5.9
Level 45	2(1.63)	2(1.89)	3(2.47)	8:41	5.9
Level 50	2(1.55)	2(1.82)	3(2.38)	8:23	5.8

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

Eternatus1.65

A prepared party

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

2 trainers at level 40

Eternatus1.65
Kyurem (Black)1.78
Necrozma (Dawn Wings)1.94
Kyurem (White)1.99
Palkia (Origin)2.18
Baxcalibur2.21

A mixed local group

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

3 trainers at level 40

Darkrai2.40
Dragapult2.44
Kyurem2.47
Palkia2.48
Salamence2.52
Lunala2.57

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)

Ice Fang + Ice Burn

5. Palkia (Origin)

Dragon Tail + Spacial Rend

6. Baxcalibur

Ice Fang + Glaive Rush

See the full ranked counter list for Giratina (Altered) · 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.