Counter to Dragonite

Cloyster IV 13% – prestiger, now in an ideal CP range

Jynx with FB/Avalanche is probably the best in-game overall, but remember to dodge.

Cloyster IV 91% – attacker

Cloyster IV 89% – not that good, don't power up it

Piloswine – all very decent, you may want to pick the 60% IV one to be an excellent prestiger; and others being attackers

Sneasel may also work, but seems like a weaker Jynx in most cases

The things above aren't real in-game experiences.

Either of the first 2 Cloyster will rip thorugh a DNite....mine do.

I can not speak from experience about Piloswine, but on paper, all of those should do a job on Dragonite.

1392cp 91% with ice shard & avalanche and hatch a Smochum with good IV and hope for frost breath/avalanche (or maybe you'll find the Lapras you're looking for ahahh)

Pillowswine with PS/A is a monster when it comes to handling Dragonite. Energy fills so fast with powder snow. As a straight attacker and not a prestiger he is worth powering up to level 30. I do not have a Cloyster with avalanche so not sure how it works but I imagine it is very good also. Personally don't like Jynx that much.

Dragonite's biggest enemy is Steel Wing and Hyper Beam.

In my area, Dratinis are common (so Dragonites dominate the gyms) but Ice species are rare, so besides my Cloyster and Jynx (both hatched, level 30 wonders with double Ice moves), I use Slowbro with Conf/IB and Gyarados with DT/OR for Dragonites with SW, plus Pound/PR Wigglytuff and ZH/DG Clefable for Dragonites with DB/DT. In fact, this team once took down a gym with nine Dragonites!

Any of those will rip through a dragonite. I would max the 91% cloister for enemy attack. Then, strategically power the rest to cover the 1200 to 1800 cp range for prestiging.