What would a maxed Gyarados be useful for?
Upon reaching level 38, I maxed out two Machamps (perfect and 98%), but all my other attackers and defenders remain at level 30. Currently walking Chansey and seeking crowdsourced Hatch 5 Eggs research to turn my 96% hatchling into a maxed Blissey (gyms here are highly competitive).
Magikarp is my favourite species and during the recent water event, I repeatedly did its quest, earning a shiny wonder and a 98% non-shiny (my previous best was 93%). With 1.6M dust and 2k candy, I am really tempted to max out the 98%, but 250k dust is still a lot and hard to justify spending on Gyarados.
What would a maxed Gyarados (with WF/HP) be useful for? There is an obvious role in Onix solos, where Gyarados is barely viable at level 30 but a solid winner at level 40. Its only relevant matchups on gym offence are Rhydon and Steelix. For gym defence, the dust would be better spent on Chansey, Snorlax, Milotic and Lapras.
Could those with more knowledge about future generations advise how well Gyarados would fare in future legendary raids and more importantly, how secure is its position as the best non-legendary Water-type attacker?
(My best Dragonite is 91% and my best Tyranitar is 93%, so I am unlikely to max them out despite having the candy. Only using my daily free pass supplies just enough Rare Candy to take one of each relevant legendary species - including Kyogre - to level 30, but not multiples or maxing out.)
Answers
Gyarados is quite useful as a Groudon counter - even with Waterfall/Hydro Pump, it doesn't hit quite as hard as Kyogre, but it does doubly resist ground moves, so against Mud Slap/Earthquake it can take a lot of damage. It resists Fire Blast, but is weak to Solar Beam, and neutral to Dragon Tail.
Other than taking advantage of it's flying type, though, Gyarados generally takes a back seat to Kyogre. But if it's one of your favorite pokemon, have fun with it. It also has the advantage of not requiring rare candy, and requiring only 1 km to get a candy, so it's easier to power up than Kyogre.
Finally, if/when we get Mega forms, the Mega Gyarados gains a dark typing, and could be quite powerful. I caught a 100% Magikarp during the water event, and I'm waiting to evolve it until we learn how Mega forms work. Maybe it won't make a difference, maybe it will, and I have two good water Gyarados, and a dark Gyarados, powered up, so I don't need another.
Not much use for a maxed gyarados right now but if you don't have the RC for 6 maxed Kyogre this is your next best bet.
As far as future proofing is concerned, Gyarados remains relevant. Palkia is going to challenge Kyogre and Gyarados will drop at least to 3rd but Palkia is also going to require RC investment.
(On defense) Empoleon might be a challenge- is arguably the best Gen4 starter family with a steel typing. I won't hit as hard as Gyarados but has a boatload of resistances for general usability, but has critical flaws in what you usually use water for attack. It does not resist fire and weakness to ground (although gaining resistance to rock). It can probably serve a lot more diverse roles than Gyarados does though.
Gyarados possesses a double resistance to Ground, which certainly helps in raids such as Golem, Rhydon, and Groudon. It also takes neutral damage from Grass, which helps when random raid bosses have Solar Beam for no apparent reason. These typing advantages push it's TDO higher, but only to a level slightly below Kyogre. However, that alone makes it very useful and a potential attacker.
Although it will be relegated to the food you leave at the bottom of the freezer in the upcoming Gen 4, (especially if Swampert and Feraligatr get Hydro Cannon and Gyarados doesn't) it's candy is easy to find, not requiring you to do raids en masse or get lucky hatches.
I left my hundo with double-dark moves for focus blast mewtwo, and have a couple other 96-98% powered up from old gym days, with water moves as a "budget Kyogre" as others have written. Not useless. Also, with 1.6M in dust, it's really OK to loosen the purse strings a bit and spend on some favorites! There will always be *something better* on the horizon, that shouldn't restrict you too much. I'm a hoarder by nature as well, but have found my team lasts longer than I thought by maxing some out, and still have 1M in dust.
There are a couple water types that can outclass regular Gyarados:
Starters with Hydro Cannon (any but Blastoise)
Palkia with double water moveset (gen 4)
Keldeo with double water moveset (gen 5)
Most water type megas (Blastoise, Swampert, Sharpedo; gen 6)
Non-Hydro Cannon Ash-Greninja (gen 6)
Volcanion (gen 6)
Wishiwashi (gen 7)
Obviously, Gyarados gets a mega too if it is implemented which is then only outclassed by Hydro Cannon Mega Swampert, Ash-Greninja (glass canon), and (Primal) Kyogre.
However, bear in mind that water is not going to be used a lot against legendary raid bosses. Many that are weak to water, are double weak to another type (Heatran to ground (gen 4), Landorus to ice (gen 4), Nihilego to ground (gen 7), and Stakataka to ground and fighting (gen 7). You then have Terrakion (rock/fighting, gen 4) and Blacephalon (fire/ghost, gen 7) left with a single weakness to quite some types.
TL;DR: As a water type it's a sound investment in the near future, but water type as a whole isn't that great against the future legendaries.
