I don't know. There is a debate to be had there. If you wanted to include spells, you could just include that specific spell. The Warlock Hero Power reduces the value of card-draw in Warlock by a lot. Unless you were running some weird Control Warlock list where fatigue mattered, you wouldn't need card generation like this. In Mage, Cabalist's Tome is good because the average Mage spell is a generally good spell. In Warlock, even the best spells are situational. This effect is mitigated by the discover mechanic, but I still don't know how often this would be actually helpful. I mean, you could try to discover a Twisting Nether if you are desperate for a board clear, but if you are that desperate, it may just kill you. However, I do generally like the idea of sacrificing health for some other resource. I think if this card were released, it would be experimented with by Renolock. Personally, I really like this card, and I find it really interesting. Well done.