Drain Soul

Drain Soul steals the soul from the enemy. If the enemy dies while channeling, and yields experience or honor, the caster refresh his Soul shard.

Table
Drain Soul is available at level 10.

Tips and tactics
Use when an enemy is almost dead to maximize the damage multiplier. When raiding Affliction, substitute Shadow Bolt with it when the boss is below 25%, keeping your DoTs up at all times. This results in extraordinarily high DPS when coupled with Haunt, which amplifies its effect. This effect is comonly refered to as "Drain Soul Execute", or DSe for short. Borrowing from the Warrior ability execute, which has a similar effect.

Use it on enemies that are green and you can farm Soul Shards easily.

As of patch 3.1.0, when the proc was added, you can farm soul shards from training dummys.

It is advisable for warlocks to always keep a few Soul Shards available at all times. A lot of key spells require them.

Drain Soul can not be reflected.