Okay, so I've reached W5, which is supposedly where the Bloodbound skill tome lies. I'd like to get it, but no matter what, I just can't seem to open it. The requirements say I have to kill 106 giants (don't have to be frozen or cursed, thank god) within a range of 11.1. The sad thing is, where I placed the gem, I had an extremely limited timespan in which I had to kill the giants. I got almost half of the requirement, but then the level ended.
How should I go around opening it? Should I level up a bit and then come back?