>>37146475It's only speculative, it's yet to be seen if PvP will be offense or defense oriented.
A CP 1500 Blissey might be untouchable and defeat opponents faster than it can be defeated, but I doubt it. Meteor Mash Metagross hard-counters it.
CP caps are a great equaliser, anything that can reach a 1500 or 2500 CP cap will be on an even playing ground as other things based on their base stat distribution. Those that favour high attack and/or have access to superb moves are going to be better than those that don't.
This means that in an Ultra League situation Hydro Cannon Blastoise may actually be better than Gyarados, or even Kyogre.
However, that's a level 40 Blastoise vs a level 21 Kyogre.
Feraligatr will also get access to Water Gun/Hydro Cannon and has a more favourable stat distribution, so it'll out DPS Blastoise and probably be a PvP king.