The Diablo 2 Wiki
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Slows Target

From Diablo 2 Wiki

Slows Target is a Special Modifier that slows the movement and attack/casting rate of the affected target. Targets that are slowed turn blue as though they were chilled, but there is no cold damage associated with this modifier.

Calculating the total amount a monster or player will be slowed is fairly complicated, and requires knowledge of their initial speed, their type, and must also factor in properties such as Extra Fast monsters, Holy Freeze, Fanaticism, and more.

The effects are capped in various ways:

  • 85% against attack speed
  • 75% against run/walk
  • 50% per source* (equipment/different players/skills/etc) against players/act bosses
  • 90% per source* for normal monsters but at 90% for them.

* A "source" is an item with this modifier on it. Multiple "sources" add up the slowing time, so using multiple items that grant Slows Target will cause a cumulative effect, and make the target really slow.

Caps on Slowing

The most slowing possible to a player is limiting their speed to one yard/second. (Default is 4 y/s.)

The most slowing possible to monsters varies by their different base speeds, but it's generally around 25% of their normal movement speed. (This is less than the 90% slowing from each item, but monsters with Extra Fast and/or Fanaticism will be much faster than usual to start with, so can be slowed more than 75% total.

Attack rates can't be slowed below 15% of the base animation rate for the attack, but as with movement speed, monsters that have a faster than usual attack might require multiple items of slows target to reach their minimum speed.

Casting rates are effected just the same as attack rates.

Note that Slows Target is banned in most PVP duels, since it is so powerful it completely unbalances some matchups.