Countering Typhlosion

I attempted a duo, but was unsuccessful due to it having solar beam which deals super effective damage to all possible super effective counter types (water, rock and ground).

If you come up against one of these, make sure to use super effective types with super effective movesets, that also have a secondary typing that resists grass type moves, a good example of this is Gyarados as its flying type characteristics make it take neutral damage as opposed to super effective damage.

I dont think Gyarados has a good enough attack to kill it on time
And I was right, Gyarados falls just short of a duo outside of Rainy Weather
And in Rainy weather, its still very unlikely without a friendship boost
And 6 Gyarados will die anyways, so the boss’ health regeneration and the time it takes to hop back can cause severe problems

Gyarados was lasting much longer than Kyogre though, was able to get an extra one or 2 charge attacks in each before fainting.

But he doesnt have enough power to do a duo, so its effectivelly useless
Actually, a duo without friendship and weather boosts is impossible against Solar Beam