Each attack on the same creep penetrates deeper through its armor. Per attack 4% of this tower's attack damage won't be reduced by armor resistances. This effect stacks up to 5 times.
Level Bonus: +0.16% damage per stack
Lightning Shield
As the zealot gets pumped up debuff durations are reduced by 6.5% with each stack of Zeal.
Zeal
Each attack works the Zealot into a greater frenzy, increasing his attack speed by 2% from each tower in 175 range. These towers have their attack speed slowed by 2%. Both effects stack up to 5 times and last 2.5 seconds. The attack speed amount reduces slightly with more towers. Only towers that cost 460 gold or more are affected by this.