I found that eating rocks might've brought me EXP, but it didn't sate my physical hunger, and after this forceful evolution, it only grew stronger. A single critter wasn't enough to sate it, but I still had to put my EXP to use before I went to hunt again, even if my stomach protested.
So I did that in a hurry.
Most of my EXP was eaten by levelling up 'Frost Wind Claws'. To level up a single ability with base cost of 1 EXP from level 15 (or close to it) to level 20 cost approximately one million EXP. If the base cost was higher, I had to multiply it by the number.
'Frost Wind Claws' had base cost of 22 EXP, which meant that even the huge amount of it I got from the magic rock wasn't that huge when you thought about it. But it was worth the cost—when I got my upgrade, there was an option I just had to pick immediately.
I abandoned math. And socium.