Your Maps have +(3-5)% chance to contain an [ContainsAbyss|Abyss] per 2% increased Pack Size

What this record tells you

This is a prefix modifier available from level 68. Its listed spawn tags determine which item families can naturally receive it.

Positive spawn weight means the modifier is eligible for that tagged item family. A zero weight blocks it for that tag. Weight is relative—not a simple percentage by itself.