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 Tirtouga's top six counters needs 1.89 trainers (round up: 2), and a mixed lobby of ranks 13-24 needs 2.33 (round up: 3). The raid timer is 300 seconds and one prepared trainer alone would take 8:54. No level in this range makes it soloable with a prepared party. A duo works from level 35.

Tirtouga · Shadow Tier 5

waterrock

Weak to

grassfightinggroundelectric

Boss CP: 23,155
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 Tirtouga 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(2.37)	3(2.68)	4(3.24)	12:40	6.0
Level 25	3(2.05)	3(2.35)	3(2.87)	11:05	6.0
Level 30	2(1.84)	3(2.07)	3(2.50)	9:46	5.9
Level 35	2(1.74)	2(1.98)	3(2.41)	9:21	5.8
Level 40	2(1.67)	2(1.89)	3(2.33)	8:54	5.8
Level 45	2(1.63)	2(1.83)	3(2.22)	8:40	5.7
Level 50	2(1.55)	2(1.77)	3(2.14)	8:21	5.5

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

Kartana1.67

A prepared party

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

2 trainers at level 40

Kartana1.67
Shaymin (Sky)1.86
Zarude1.88
Rillaboom1.94
Xurkitree1.95
Roserade2.01

A mixed local group

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

3 trainers at level 40

Chesnaught2.17
Shaymin (Land)2.21
Venusaur2.24
Tangrowth2.29
Celebi2.31
Torterra2.31

The party these numbers assume

1. Kartana

Razor Leaf + Leaf Blade

2. Shaymin (Sky)

Magical Leaf + Grass Knot

3. Zarude

Vine Whip + Power Whip

4. Rillaboom

Razor Leaf + Frenzy Plant

5. Xurkitree

Thunder Shock + Power Whip

6. Roserade

Magical Leaf + Grass Knot

See the full ranked counter list for Tirtouga · 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.