I have crossed the 300th level in just two and a half hours; my speed had barely slowed even after strong Dimond started to show up. It did not matter; If it is Platinum, Diamond, or regular Adamantine, everything is the same for me.
In the 300 levels, I had crossed, I had received three rewards, on which is an ax, a shield, and as strange as it sounds three seeds. Those seeds are of the very rare lily, called from Tranquil Lily Family; these lilies produce a smell that could calm one's mind.
I had directly added them into my Constitution formation, but seeing they are not making much difference, I took them out. I could sell them in exchange for herbs; if I am lucky, I might be even able to fill 1% of constitution storage.
Since my constitution had upgraded Level 10, I started adding stuff for Level 11, and there is quite a big chance that I might be able to gather enough materials in the Tower that might be able to upgrade my constitution to Level 11.
