Zen Headbutt/Thunder Mega Latias Duo Raid, No weather boost, No Relobby, 20% Friend Bonus

Mega Latios and Mega Latias are available as the special raids in Pikachu Air Adventure events.
In 3 months ago, we have defeated Mega Latios and Mega Latias as Duo Raid, where Mega Latios was defeated without weather boost and Mega Latias in Windy weather. Especially for Mega Latias, we have showcase the effectiveness of Shadow Dragonite, especially for its Dragon Breath/Draco Meteor moveset with Party Power.
Back in that raid, a full team of Shadow Dragonites with 15 attack IVs and 3 stars total IVs are used. If you had watched that video, you might have questioned - There are quite a lot margin at the end, are high IVs Shadow Dragonite necessary at all? What's the point to farm a full team of high IVs Shadow Pokemon?
Well, there was one detail we have deliberately dropped for that raid, because it is extremely hard (or practically impossible) to make it happens. In fact, Mega Latias was possible to be defeated as Duo Raid without weather boost in theory. In that case, Shadow Dragonite's IVs did matter.
In no weatherboost scenario, a dodged Thunder would deals 20 to 21 damage against Shadow Dragonite, and Dragon Breath/Zen Headbutt would deal 10 or 12 damage regardless of its IV. Shadow Dragonite's HP ranged from 175 to 188, depends on its IV. Observing these numbers, it is not hard to tell that a perfect IV Shadow Dragonite would be able to take one more fast move compared to a Shadow Dragonite with low HP/Defense IVs. Yes, that extra fast move is exactly where it matters. Specifically, that extra survivability allows Shadow Dragonite reaching 3rd Draco Meteor consistently, which is mandatory to have any chance on defeating Mega Latias as Duo Raid without weather boost.
Of course, it does not requires to be perfect IVs(15/15/15) for that. Specifically, a Shadow Dragonite with at least 9 Defense IV and 7 HP IV (X/9+/7+) or a Shadow Dragonite with at least 10 HP IV (X/X/10+) would be able to take that extra Dragon Breath/Zen Headbutt.
While there is no Dragon Breath breakpoint from Shadow Dragonite to Mega Latias, if the raid run optimally (where Shadow Dragonite does not use any extra Dragon Breath), Shadow Dragonite with lower attack IV would deals less damage with Draco Meteor such that Mega Rayquaza would requires to use extra Dragon Tail to compensate it. To avoid extra Dragon Tail usage, 6 out of 10 Shadow Dragonites among both team has to be 15 attack IV, with the remaining 5 having 14 attack IV.
While it surely is not as strict as the team assembled, it is not exactly trivial to find one Shadow Dratini with those spread (14+/0 or 9+/10+ or 7+). Unfortunately, we didn't make it after numerous attempts, with only a few comes close at the end since Party Power had never been fully functional.
However, with season World of Wonders starts, friendship damage bonus is now boosted to 20%. Thankfully, that extra 10% friendship damage bonus was enough to be the final push for this Duo Raid.
This time, Mega Rayquaza and Shadow Dragonite are challenging Mega Latias as a Duo Raid without weather boost, utilizing Party Power and the seasonal friendship damage bonus. As stated in Mega Latias Duo Raid, Mega Rayquaza is lacking behind from Shadow Dragonite in DPS, such that it is only used at the end to avoid rejoining.
With the favorable IVs spread, Shadow Dragonite tends to went down naturally soon after it fired a Draco Meteor. However, since Mega Latias would pick its move randomly, fast moves dodging are required occasionally to avoid getting hit by Thunder under Draco Meteor cooldown or to ensure Shadow Dragonites can fired the last Draco Meteor successfully. In the other hand, Mega Rayquaza would need to time both of its Dragon Tail/Outrage very carefully such that it can defeat Mega Latias at the end. Overall, it remains to be an extremely difficult raid, despite it is 10% easier than the theoretical limit.
A little bonus of comparison video between Dragon Ascent Mega Rayquaza and Shadow Dragonite is appended at the end. With Party Power, Shadow Dragonite can now tie with Dragon Ascent Mega Rayquaza without it, and only slightly behind Mega Rayquaza with it.
Team used:
CP 4287 Shadow Dragonite - Lv50 15/15/15 Dragon Breath/Draco Meteor
CP 4278 Shadow Dragonite - Lv50 15/15/14 Dragon Breath/Draco Meteor
CP 4267 Shadow Dragonite - Lv50 15/13/15 Dragon Breath/Draco Meteor
CP 4258 Shadow Dragonite - Lv50 15/14/13 Dragon Breath/Draco Meteor
CP 4248 Shadow Dragonite - Lv50 15/14/12 Dragon Breath/Draco Meteor
CP 6458 Mega Rayquaza - Lv50 15/15/15 Dragon Tail/Outrage
CP 4248 Shadow Dragonite - Lv50 15/13/13 Dragon Breath/Draco Meteor
CP 4249 Shadow Dragonite - Lv50 15/15/11 Dragon Breath/Draco Meteor
CP 4238 Shadow Dragonite - Lv50 15/12/13 Dragon Breath/Draco Meteor
CP 4228 Shadow Dragonite - Lv50 15/11/13 Dragon Breath/Draco Meteor
CP 4219 Shadow Dragonite - Lv50 15/14/9 Dragon Breath/Draco Meteor
CP 6535 Mega Rayquaza - Lv50+1 15/15/15 Dragon Tail/Outrage

[@pogoraidsgameplay2527]

This definitely shouldn't have costed only 6 attempts in general and it only happened because every single details in this raid had been meticulously investigated through the 600+ failure attempts in February. And honestly, this is also a fairly lucky seed until 5th Shadow Dragonite where Shadow Latias kept refusing to use Thunder.