Lol I only just redownloaded FGO so none of these means anything to me.
Side note: Can you promote units like in FEH? I have 3 star Zero Lancer and 3 star FSN Lancer and would love to use them. Also have 4 Star FSN Archer lol
Boudica you ever heard of clothes?
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Basically, there are events, like the ongoing Fate/Zero event, and there are going to be quite alot. Basically, the way they work is that they are a bit of a mix between a "collect-a-thon" and the FEHeroes Tempest Trials. In the case of the Zero event, it also includes missions, kinda like FEHeroes' missions like "defeat Colorless foes with an Infantry unit" and whatnot.
But basically, you are trying to collect "currency" to buy stuff from the shop and having certain units increases the amount of currency you get, kinda like with Tempest Trials that using certain units will give more points. The event also has a story mode going on, some easy and straightforward. Others require you to do certain missions to unlock the story, like in the case of the Zero event and the Kara no Kyoukai event. So basically, you are trying to get through the story as well as collect as much currency as possible to get materials for your Servants or other items, like mission requirement items.
You don't need to be in a rush. The Zero event is lasting for 3 weeks and if you can use up all the AP that you can get within the week, you can potentially clear all to next-to-all the missions and whatnot without using any Apples or whatnot. So you can take your time if need be.
And yes, you can promote units, but it's a different process compared to FEH. Whereas FEH only has 2 materials needed for promotion, each Servant in Grand Order requires their own materials needed. Some share the same materials, others can have their own materials. But basically, absolutely no where near as simple as FEHeroes.
Also, it's not a case where "ascending" increases Star Level, like with Heroes. Basically, Servants have 4 stages of "Ascension" and ascending them increases their level. Also, in order to ascend them, besides the materials, they have to be at their latest max level. Every time you ascend, they get 10 additional levels.
-For 1 Stars, they go from 20 to 60 altogether.
-2 stars, 25 to 65.
-3-Stars, 30 to 70.
-4-Stars, 40 to 80.
-5-Stars, 50 to 90.
Also, ascending them does change their outfit, for most Servants. Welfare servants don't get an outfit change. But yes, ascending Boudica will give her a much
much better outfit compared to that stupid outfit she starts with. All Servants you get from the Gacha get two outfit changes. One at first Ascension, the other at 3rd Ascension.
Anyway, working through the Fate/Zero missions will give you materials for your Servants to allow you to ascend them and whatnot. So take your time and just work at your preferred pace.
And, unless your name is Phantom of the Opera or Benkei, you should just focus on using your favorite characters.
Benkei is at least usable, thanks to his Tanking skill and for being an Arts-based Servant. Phantom and Caster Gilles, not so much. Mephistopheles as well, but at least he has a niche against enemies who use alot of buffs.