12k 4* (15k if not same class or all class), also need 1 grail per 2 levels after 90 and 30 servant coins per 2 levels after level 100. Lottery events are a good chance since boxes give 4* exps along other nice rewards. Also leveling during x2 exp, xN success campains helps a lot.

Oh wtf that’s a ton

I’m gonna stick to doing my skills

Best way to do it is to save all those 50 bundles of embers in the inbox and then do some ember farming on top during a 1/2 AP and 3x success campaigns (usually during Anniversary)

It's how I do it.

How should I get the embers?

Monthly MP shop and events have a pack of 50 5* Embers, it adds up throughout the year.

That’s only 50 a month though… that won’t make even a dent in the exp i needed

12k 4* embers isn’t gonna be taken care of by 50 a month