In our interview with Blizzard's Associate Game Director Morgan Day and Lead Narrative Designer Steve Danuser, it was revealed that Dragonriding will be further expanded upon in Patch 10.1: Embers of Neltharion with a new ability called Ground Skimming. Ground Skimming allows you to recharge your vigor while flying near the ground which is a departure from current Dragonflight where the only way to rapidly recharge your vigor is to to fly at really high speeds. In order to obtain Ground Skimming, you'll need to collect the new Dragonriding Glyphs found throughout Zaralek Cavern.
Dragonriding and the ability to Ground Skim will likely be available Day 1 of Patch 10.1. Read the full quote below for more context and Blizzard's philosophy on Dragonriding in Patch 10.1: Embers of Neltharion.
Elizabeth from BlizzardWatch: I'm wondering if you can tell me a little about flying in Zaralek Cavern? Will we need to re-earn it or will we be able to fly right in? Morgan Day: Definitely you'll be able to Dragonride from moment one. That feedback is something that we've heard loud and clear from previous expansions.We didn't want to make you re-earn Dragonriding. Being able to in that opening experience take your dragonriding mount and fly through this huge hole in the ground that the Incarnates have created to bore their way into Zaralek Cavern. You'll be able to do that minute one.
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