Guild Wars 2

[Slime Barrier]
Covers the outside of a creature, until this is removed by non-crowd control conditions, from a source with equal or greater level of a specified condition attribute the creature is immune from damage. More slime exudes over time. Refer to Tequatal/Scales.

[Reflection Aura]
Surrounds the creature, until this is removed by non-crowd control conditions, from a source with equal or greater level of a specified condition attribute the creature will reflect all ranged damage back to the source of the damage

As level 80 zones, suggested required minimum condition damage
⁴⁰⁰ – removes 1 point of the effect / application
⁸⁰⁰ – removes 2 points of the effect / application
¹²⁰⁰ – removes 4 points of the effect / application
¹⁶⁰⁰ – removes 8 points of the effect / application

When the effect is removed, the special defence is discarded and normal damage can resume, just keep the effect tick/regen down by repeated application!

Such effects can be overcome by swapping in/out items or by a build that has at least 400 condition damage ( not a lot tbh, could easily be done using adornments ). It also provides work for other build types

This kind of effect could work with other attributes

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Yes. I have had some involvement in a non-for-profit mmorpg, and understand credit sinks.

Definitely sounds like something to make things take longer to kill, so… no. Bad idea on those grounds. Things don’t need to take longer to kill than they already do.

- very complicated mechanic
- forcing you to get gear / traits to reach a specific cap of some attribute
- no benefit for gameplay

sorry but definitively no

things like your slime barrier or reflection aura are good mechanics for bosses if you can remove them by doing something specific like using some lasers at the same time or whatever but not if you remove them just by having some attribute of a certain level.