The actual description for the achievement is as follows:
As Cupid Kill three or more gods with the damage from Heart Bomb.
Cupid's first ability (
or 1) is his Heart Bomb. While the description leaves a bit to interpretation, you must kill three enemies with a single heart bomb explosion
. During our session we attempted to net the achievement with three separate heart bomb kills but it did not pop the achievement. This means you will need to have three weak enemies all in extremely close proximity to each other and kill them with the single explosion.
Earning this achievement legitimately will prove to be a monstrous task. There are very few occasions where enemies with be grouped together in numbers of three or more, and even less likely will they all be low enough health wise to die from a single heart bomb explosion.