How should I get back into the game?

Log in before the alter ego extravaganza ends. Get Koru-moru, Adelheid, and Qultada at the very least. I think Ferreous Coffin is also available from the sparks NPC. Those are the timed exclusives you want to make sure you get (Koru-moru has been unavailable for almost a year).

From then on out, you can level pretty quickly via a trust NPC party + Grounds of Valor pages. GoV (dungeon) pages are usually better because the xp increases as you continue to do the page, and you get additional buffs (once per game day). Also make sure to use your xp rings, or grab one from the conquest vendor if you don't have it. They were recently buffed and offer a bigger total xp bonus.

As for which job to choose, I favor dancer for various reasons. But you can honestly go with whatever you want. Dancer is a very strong solo job that will allow you to solo many things at level cap, if you should need to do so. It's also a great support healer and can dish out some mean damage if you're not forced to make up for a shitty healer.

Leveling these days goes by fairly quickly, and once you get to the 70's you can participate in worm parties as an actual participant (if you want) or you can continue to level using GoV pages.

Make sure to check the blue chest in port jeuno next to the abyssea npc's to get the starter kit, and start the abyssea questline so you start generating stones (if you have not). I believe this can be started by any job over level 30. Also make sure to start record of eminence and unity (when able) so that you have extra sources of XP/sparks/unity accolades. Don't go out of your way to do the zone RoE quests as the benefits are minor. Mostly do the combat RoE, and pick up the crystal/geode RoE based on what you're killing. Check the zone RoE kill quest for the area you're doing pages in to see if it lines up with what you're killing for some extra xp.

Most of this game is looking up information on your own. BGwiki and ffxiclopedia are great resources that many people use. Should you need more info on anything I mentioned check out those sites.

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