Quantum's Take

Harley Quinn is one of the most important early champions for non-spenders and lite spenders. Since you get a copy of her through the 7-day login reward, it means that any additional shards allow you to build her abilities. She does decent AoE damage, especially with her legacy weapon, which is given to you early on in your playthrough. She does taper off as you get access to limite mythics, but I think she will see a resurgence as soon as there's a renewed focus on Suicide Squad champions.

Damage Type

Physical

Sources where available

The Bleed, Motherboxes (Purple +), Random Mythic Shards, Custom Mythic Shards, Daily Deals, 7-Day Login

RavenHrt's Transmute Priorities

ATK, HP, Energy Gain Bonus

Recommended Legacy Pieces

Honkin' Huge Hammer

Not So Huge Hammer

Multiversal Force Upgrades

Manic Episode - Enhanced

[Manic Episode] additionally reduces the target's Physical DEF by [%] for 5s.

Escalation - Enhanced

Increases Harley Quinn's ATK.

Special Physiology - Enhanced

Increases Harley Quinn's Max HP.

Ultimate

Self-Actualization:Relase Self

Harley Quinn unleashes her full potential and enters a [Self-Actualization] state for 10s, dealing Physical DMG equl to [%] of her ATK to the target and all nearby enemies. [Self-Actualization]: Increases ATK by [%] and enhances attacks to deal AoE damage in a small area.

Global Skill

Reckless Abandon

Increases [Suicide Squad] Champions' ATK.

Skills

Manic Episode

Deal Physical DMG equal to [%] of ATK to an enemy

Escalation

Gains HP equal to [%] of Damage Dealt. All [Suicide Squad] allies gain HP equal to [%] of DMG dealt

Special Physiology

Gain [X] Energy per enemy defeated