Is Rayquaza much easier than Groudon and Kyogre?
I've read that it's a really easy trio with Dragonites, Rayquaza himself, and the Ice Conglomerate.
Instead, the challenge would be to find people that are willing to attempt a trio, or even 4 man. Same problem with Ttar.
Answers
If you think about it, Moltres has a defence stat of 184 and was duoed before with Golems exploiting the double weakness. Rayquaza has 170 and also the double weakness.
Ice mons, particularly Jynx and maybe even Articuno with Blizzard/Cloyster with Av, can exceed the DPS of golem, and the ice mons attacking into a target with lower defense. Dragonite with its dragon sets can also get close to Jynx level DPS. The plus side for Golem, of course, is that it resists the fire moves.
Time will not be an issue, and especially with battle parties now, if you have a full complement of 12 pokemon and all it takes is a swipe to jump back in, a duo should not be that hard.
In a word: YES
Anything with a double weakness is easier to counter than things without a double weakness.
You will also see some potential double resists at play due to Flying being resisted by Rock/Steel. DT/SE Aggron will double resist + offer SE attacks.
There's nothing that double resists Kygore's attacks + offers SE effective.
We say similiar with the Dogs. Entei took 1 less person then Suicine for same effect. Not because Suicine was stronger then Entei, but rather because better counters existed for Fire Pokemon then exist for Water Pokemon.
Aggron doesn't have enough offensive presence to kill rayquaza with sub-optimal group sizes. Also Suicune was harder to kill because it has higher defense than entei. Entei's defense is pitiful for a raid boss while Suicune's defense is its speciality. HP doesn't count to the bulk of a raid boss because they have the same hp, it's the defense that does.
Aggron is a great option for flying and rock sets, whereas Gardevoir is a great option for double Dragon sets. Both should serve as anchors placed in the rear of the group. Because fainting out will definitely happen, an anchor is good because some phones take a very long time to rejoin, even with battle parties (Mine takes upwards of 20 seconds).
That being said, if you're attempting something stylish like a duo or trio you may want to do without them.
