I'd still classify this as a bug. Currently the spell follow two rules
1. The damage of the spell depends on the roll (the higher the better)
2. Whether or not the spell will land on a monster depends on the monster's level being a multiple of the dice rolled.

Really, only one of these rules should apply if the blood pact is going to be useful. Either make it random damage that can affect all enemies (do this by only following rule 1). Or make it do massive damage to enemies that are a multiple of the roll that was made (do this by only following rule 2). I would prefer that the second rule be dropped. I'm in favor of chaotic damage, but there's too little chance that this spell will do sufficient damage (if any) to its target.