Strides of Heresy

Strides of Heresy is a Lunar item, part of the Heresy Set, that can be obtained by completing the Blockade Breaker challenge.

It replaces your utility skill (Shift by default) with Shadowfade, an ability that gives you complete invulnerability, movement speed, and a large heal at the cost of being unable to attack. Using Shadowfade is very good for retreating from a dangerous situation to recover and reassess.

Strides of Heresy's only overt downside is that it replaces your default utility skill with a very specialized alternative. Additional stacks of Strides of Heresy only increase the duration and heal of Shadowfade. Excessive stacks can result in more time out of reality than in, which can be excessive and boring without something like N'kuhana's Opinion.

Does not grant immunity to the Shrine of Blood nor the damage taken when outside a node's barrier in the Void Fields.

Synergies

 * The Hardlight Afterburner grants 3 charges and reduces the cooldown to 4s after the effect. Since the first stack's cooldown runs even while a second use is active, this skill can used almost indefinitely (in theory 18s straight, and then 75% of the time) to escape danger. This also makes the flight duration comparable to the Milky Chrysalis.
 * This item is especially useful for Commando and REX (without its alternate utility skill unlocked), since the skill it provides is (debatably) an upgrade over their default utility skills. For other characters, such as Huntress and MUL-T, this item is more of a toss-up, and up to user preference. On everyone else, the skill replaces a core, iconic part of their kit (such as Engineer's Barrier). Characters like Mercenary and Loader have their damage outputs substantially lowered as a result of having their shift skills replaced.
 * The Artificer gives up a powerful attack for this effect, but can take unique advantage of the flight effect with her passive. Hovering throughout the cooldown effectively grants her slow but unlimited flight.

Trivia

 * The foreign leg resembles that of the Alloy Vultures.