Draw chances differ per banner. (This is off top of head; someone should link the actual excel sheets people datamined to cross-check because I could be completely wrong on some points)
I think the easiest way to describe it that has held true for each banner (could change in future) is:
- total chance for 5* is 10%
- the chances for items in the banner are 1% each
- the chances for other character-specific items are hilariously low
- there's a small pool of more generic items (Genji gear, Danjuro, Judgement Staff, Regal Gown) that pad out the chances so that 5*s are 10% total.
This usually means they actually have a higher chance to roll than the banner items (crossed-out is not applicable anymore with the amount of generic 5*s. They're all lower than 1% chance now)
Basically pulling anything that's not genji armor, danjuro, judgement staff, regal gown or current banner items approach one-in-a-million shot (lol)
I'd say that the chances of pulling something you want is pretty low regardless of if you save all your mythril for it, or even spend $$$. That being said though, everything is relative and even a pretty low chance is better than a nigh-impossible chance, so you'd still want to save your mythril for a character weapon you really want, then pray to RNGesus and prepare to be disappointed.
And yeah, unless you're struggling to clear stuff and a few 3* items would really help (this only really applies to the first ~2-3 weeks from starting the game, really) you'd do better to save for 11-pulls. Having 1 more shot at a low chance is still better than not having it.
edit: found it
https://docs.google.com/spreadsheet...EVgnpdyxy9kRzYeyjhC2wDFgCM/edit#gid=870050672
As you can see, this 1% thing meant that when Regal Gown was featured on Terra's banner you actually had
less chance to pull it than when you tried some of the other banners. WTF DeNA lol
. My main group is maxed and I don't want to create any specific abilities atm).
