Ok, there's now a bigger slime blob right behind the horde of zombie-slimes.
Unlike the first big blob, this second one was at least two and a half times in size and the slime core seemed to keep rotating around in an orbit in the centre of the slime mass.
I wasn't sure why that was happening but that's what I saw.
The good thing was that there were less zombie-slimes now so Shadow Odeta, Emilia, Lisa and Eins were dealing with them much more easily than earlier.
That gave Delmare all the time she needed to tie two Mana Crystal's to her arrow and letting Eins pour her mana into one while she handled the second one.
Since they were both Shadow Guards, they could easily coordinate with each other to fill the Mana Crystals at the exact same rate.
Shadow Delmare then drew her bow and took aim at the centre of the giant blob, waiting until both the Mana Crystals were near critical mass before loosing the arrow.