Dark/Fiend/Spellcaster Themed Deck

[Azkiel992]

Hello!
Which packs should I buy to get some decent cards that might be helpful in expanding the Yami Yugi idea of Spellcaster / Dark / Fiend type of monsters?
Is buying at least 1 structure deck any helpful?

[Sparse Dunes]

Tea, drops Sage's Stone
Yugi gains DM support through leveling up
Wonder Wand is a great Spellcaster support card and good draw power(gives +3 if you use it with Legion the Fiend Jester)
Magician of Black Chaos can be added

[Azkiel992]

Not sure if I will focus on Dark Magician entirely, but still - cannot find any clear advices around the Duel Link fan sites about packs for these types of monsters.
Thanks for the answer anyway, will duel Tea to get some support :)