Zimkitha's attack boost not appleied

[Guvnor]

Damage over Time (DOT) is not, nor has ever been, affected by Attack Buffs or Debuffs… Or any other status effect for that matter either.

Read here for more information on the topic:

Understanding DoT (Damage over Time)

What is DoT? While many special skills have an instantaneous affect, others cause an effect that occurs over multiple turns. Currently, these effects can last anywhere from 2 to 6 turns. Special skills that decrease an opponents health are referred to as DoT, or Damage over Time. How is DoT inflicted? Different heroes inflict DoT in various ways. This includes “Burn damage” (see Jahangir, Kelile, and Marjana) and “Poison damage” (see Oberon, Proteus, and Sartana) which is found amongst many h…