Overencumbrance

Each Dodge Roll with Ab Aeterno adds one Overencumbrance stack and refreshes the Debuff duration. Because the Slow is not limited to movement, it makes movement and skill actions take longer. Sprinting suppresses the Slow through Ab Aeterno's separate Unaffected modifier, but it does not remove the stacks.

Each stack applies a 10% generic Slow

Overencumbered is not described as only a movement-speed penalty. Its unspecified Slow applies to everything the affected character does, including movement and skill animations.

Dodge Roll adds a stack and refreshes four seconds

Ab Aeterno grants Overencumbrance for four seconds when you Dodge Roll. Reapplying the Debuff adds another stack and refreshes its duration, so repeated rolls keep every current stack active together.

The stack count is visible

Overencumbered is configured to show its count. Use that counter to see how many roll penalties are active rather than estimating from the number of recent rolls.

Sprinting makes you Unaffected by the Slow

Ab Aeterno separately makes your speed Unaffected by Slows while Sprinting. Unaffected means the Debuff can remain on the character while its effect is suppressed, so Sprinting does not cleanse Overencumbrance or stop its timer.

Stopping Sprint can expose remaining stacks

If Sprinting ends before the refreshed four-second duration expires, the character is no longer covered by the item's Sprint-only Unaffected modifier. Any Overencumbrance stacks that still remain can apply their Slow again.

The Dodge Roll defence is a separate modifier

Dodge Roll avoids all Hits is another Ab Aeterno modifier. It changes which Hits the roll can avoid, but it does not prevent damage over time and it does not change the Overencumbrance stack count or Slow value.