Drain reduces the target's attributes, reducing his power to act. Instead of delivering instant Wound Points, the Damage determines the severity of the drain caused.
There are several variants of Drain; each has a resisting attribute and a number of affected attributes. When hit by a Drain, you get Drain Rating rather than Wound Points. This accumulates like Wound Points, but is not cumulative with normal Wound Points or other types of special damage.
For every full five points of Drain Rating, the victim looses two points from a single attribute or one point each from three different attributes, as appropriate for the specific effect. Attributes reaching zero can no longer be used. Body or Reflexes attributes so reduced cause helplessness.
Drain Rating can be healed just like Wound Points can.
At the cost of a Magic point, you can do both damage and cause drain.
If you must always use this, and thus cannot use the blast power to do normal damage, the metablast is free.