It is a super tough choice between Excadrill and Zamazenta, 30 vs 35 damage received from Thunderbolt, and 1.5s Behemoth Bash vs super-effective Rock Slide.
Once again, Ancient Power deals minimal damage on Crowned Shield Zamazenta, and it means that matchup is what we would be relying on in order to survive with minimal Max Guard/Guard usage.
Unfortunately, all of Dynamax Zapdos other moves are quite hard hitting, with no "decent tank" for those moves. There is no Dynamax Pokemon released so far double resisting Drill Peck, while Dynamax Excadrill struggle to survive Electric-type moves because of its low defense stat.
When there is no "single best choice", it fall back to the choice between Dynamax Excadrill (which resist Electric-type moves decently) and general tank like Crowned Shield Zamazenta and Dynamax Blissey.
Apart from surviving, we would also need to decide which Pokemon to charge up Max Meter against Dynamax Zapdos. This is the most tricky part of this run. Both Crowned Shield Zamazenta and Dynamax Excadrill can damage Dynamax Zapdos better than the best attacker, because they used a fast hitting charged move and super effective move respectively.
Once again, we would have to calculate and compare between Dynamax Excadrill and Crowned Shield Zamazenta and see which would work better. And Crowned Shield Zamazenta was chosen this time since we expect it to be able to use more charged moves.
The attacker we have chosen is Gigantamax Gengar, which is only slightly weaker than Gigantamax Lapras while easier to build. Gigantamax Inteleon would also work for this role.
Once again, after we know how much moves we can use against Dynamax Zapdos over the course, we can tell how much damage boost we need to defeat Dynamax Zapdos. At last, 1-3 gloves helpers are sufficient, depends on how lucky you are (how frequent Dynamax Zapdos would use Thunderbolt).
by Nikaidou_Shinku