No criminal shall go unpunished in the Court of the High Elves with Prosecutor ensuring the law is followed. She joins as the rare champion as part of October Fusion Event for Maranix.
Whilst rares are generally not game changing, Prosecutor has a niche role in being quite useful for Hydra and Iron Twins. Her A2 whilst not 100% is a 3 turn 75% chance to place Decrease Speed which is vital for Iron Twins and very powerful in Hydra. This is paired with an Increase Accuracy for himself on an A3 allowing you to build him with far less accuracy to meet those high stat breakpoints. There are not many places that makes his Heal Reduction useful however the A1 does have a 30% chance to drop some Turn Meter (no where near as good as an armiger).
Prosecutor is a viable option for Iron Twins if you are lacking and may prove useful in the mid game but you will find better options in the late to end game.