How to do this and wtf is this for

[Phantom of fire]

What are the white and blue transform kits for it says for acesnsion but it only let's me use purples for that 

 

And how do I put a paint kit on a item that can be made into a legandary or mythic because it only let's me put items on it that will upgrade it

[STARWULPH]

Ascension relics are to transform a level 50 Mythic to Divine.

The white ones are for ascending ones that start at common, like Iron boots.

The blue ones are for ascending the ones that start at rare, like Corrupt light.

The purple ones are for ascending the ones that start at epic, like Hysteria.

The gold ones are for ascending ones that start at legendary, like Seraphblade.

(currently there is no way to paint an Item that is ready to be transformed)