Extracting

In the system space, Ed was holding a semi-transparent brown-gold goo.

[Divine Tree Sap]

{Special Tree Sap capable of preserving anything not excluding mana}

'Wait… So I can store mana in this?' Ed's eyes flashed as he came to an understanding.

'So that's how it is' Ed suspected the elven arrays used this sap but now he was certain!

Holding mana did not sound like much. Weren't the runes doing that already? You could draw up anything with your blood and the possibility of mana coursing through it would exist. Thus, the answer APPEARED to be yes...

All arrays relied a lot on circulation and flow. Runes that were drawn sloppily could cause an explosion depending on the type of array. The sap could help prevent this by preserving the mana in turn allowing for the creation of much bolder runes.