I have a 15-15-12 (ADS) 93 IV lvl 25 magikarp and a 15-5-15 78 IV Lvl 23 magikarp. Is it better to power up the 78 IV? I read somewhere that lowering the defense of the pokemon can maximize its DPS. I just need advice on whether this applies to gyarados.
Lowering defence can let you take more damage to charge your charge move faster. However, Gyarados is already pretty squishy, so I'd imagine you'd want the better defence to survive longer to hopefully get an extra charge attack off during the battle instead (or a couple extra fast attacks at least).
So my recommendation would be the 93.
*Most* things that are strong have a reduced defense to make up for it. IMO,+15 to a lower defense stat makes a larger difference in effectiveness than +15 to attack, especially in gym battling (rather than challenging T3/T4/5 raiding, where DPS is king). However, it's only rarely that the increased damage from an enemy hit will make a difference between hitting that 1-bar hydro pump or not. (If you're running double-dark Gyarados, it may make a difference with 3-bar Crunch.)
The cases where lower defense IV are desirable are extremely rare. To date there has only been a ONE practical application for it, which is with Golem against Solar Beam Ho-Oh.
The whole extra energy thing relies on hitting several breakpoints, which are matchup specific. I can explain it in more detail but bottom line is you should not consider it.
So go for the 93. Higher IV is better.
The current event is a great opportunity to farm Magikarp, which is a reward from the "Catch 2 Water-type Pokemon" research task.
I got a 96% Magikarp from the task yesterday but am waiting until the end of the event to evolve it (before weather was introduced, Magikarp were common trash in my biome, but the best I ever caught was 93%).
