Overload only works when your Character gets hit, so it’s only useful on floors you can survive being hit or in Battle Arena (PVP).
Fire - Ice
Shock - Poison
when you use one of these Elements on the opposite Element, they do Effective DMG (Fire weapon on Ice Map for example), which is +25% DMG.
Effective Mythic lets all 5 Elements (including Arcane) be Effective on any Map for +25% DMG for damage calculation only (Fire weapon on Fire Map is normally -50% DMG for example). Effective Mythic is still affected by Greatly Resist and Immune affixes. best if used with Prismatic Talent (Wizard), Ascendant Set (any Class), a build with 2 Elements, or +90% or better Weaken. Ignore Resist affix cancels Effective Mythic & Weaken affix.
here’s a guide that goes into detail on how these work.
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