This allows you to almost completely lock him down without any FFXIV Gil problems

Doppelganger and Dragon’s Lai Now that you’ve done the hardest set of quests in the game; you’re ready for little something easier, I’m sure. Talk FFXIV Gil to the Priest in Augury Rock at the teleported and he’ll send you on your way to complete the ascension.

Here, you’ll have to fight the Doppelganger. Although there are several strategies and ideas regarding the best way to go about killing him, I suggest going fire (if you aren’t already) and using Meteor Storm quickly. Set up your quick-bar this way:

[Flare] ¨C [Fireball] ¨C [Meteor] ¨C [Fire Storm] ¨C [Meteor Shower

[Aura of Restoration] ¨C [2 spells of your choice].

For the two spells of your choice, you can make things easier on yourself by making those spells something absolutely pointless and time consuming; such as Air Attunement and Water Attunement. 

Start off by casting Meteor Shower immediately. This allows you to almost completely lock him down without any problems. Keep your distance, and if he does manage to stand long enough to begin casting anything (likely Fireball or Flare) then start strafing.

He’ll likely try to get Meteor Shower or Fire Storm off, so when he begins casting those, just Meteor him to interrupt.

This really shouldn’t take long and likely he’ll never even touch you. Once done, you’ll get a cut scene and end you at the Dragon’s Lair.