Answers
Do we get to use the "big 19" in the battle?
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It has to be Gym3 out of your choices.
Everything else is just going to be blown up by 2-3 Dragonites, zero thought, and minimal dodging of charge moves only.
If I want to make a Gym Hard in the Sense of Damage it would be like this
1) Blissey 3kish ZH/DG
2) Clefary 2kish ZH/DG
3) Snorlax 3k ZH/BS
4) Dragonite 3k+ DT/DC
5) Lapras 2.2k Ice Shard/Hydro or maybe WG/IB (I want 1 water 1 ice to hit both dragonite and tyrantir)
6) Eggy 2.5k Conf/Seed Bomb
Now if I wanted to make the Gym hard in the sense of time consuming to hold with Golden Rasp
I'd drop either #5 or #6, move other to 6th. Put in Chansey in the other spot.
Now if I wanted to make this a Gym that lasted 8 hours and was at a long intersection.
I'd move Chansey to 1st to lower decay and make sure a car at light didn't take it out in 1 go. Keep Clefary 2nd. Put Blissey/Snorlax 3&5 Dragonite 4 and 6th spot
When making a Gym I consider the 5 Best Attackers:
Dragonite, Tyrantir, Machamp, Mew2, and Raikou
Goal being not to let any of those attackers dominate 2 pokemon in a row.
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Why does it matter? All gyms are easily taken down. However, if I had to vote I would go for #3 being the "hardest" because it's the only one with both a Blissey and a Chancey.
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(Swiftly thought and subject to further reasoning)
From hardest to easiest:
3,2,1,5,4
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