No, vials wont disappear after a mana fluid have been used.
We want Heloria to give you a touch of the old golden Tibia days.
You can sell all vials to the vendor at the Magic Shop by simply saying "vials".
Just as you were able to do in real Tibia at version 7.7!
You are also able to buy backpack of runes at the Magic Shop by saying for example "backpack of heavy magic missile runes".
I hope this was informative!
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Yes, it is possible to buy backpack of runes at the Magic Shop. A few examples are "backpack of heavy magic missile runes", "backpack of sudden death runes", "backpack of great fireball runes".