Plague (Skill)

Plague are a family of skills of the Fortress Faction that reads Unit's stat is increased by specific values, which is increased by an extra bonus for every debuff the target has, up to 5 stacks.
The only exception is Hydra, whose Plague Skill is amplified by the number of Fortress units onto the battlefield.
A Plague Skill is always the third skill, unlockable only for Purple or higher tier units.
=List of Skills=
All Fortress, without exception, possess a Plague Skill. Here is the complete list:
Unit	Skill	Description
=Hero Synergy=
Hero	Specialty	Rank	Description