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Drain usually only effects non-life attributes like mana, movement speed, attack speed or casting speed.

Draining effects are quite similar to bleed or leech/lifesteal effects, but is usually more specific, and also often requires continuous casting to drain. However, there are exceptions, and simple DoT-like debuffs that drain attributes also exist.

Some drain effects also double as some sort of leech effect, giving the caster some sort of buff.