Assassin's Stride is a Unique Boots in Diablo IV Season 15 for Rogue. It drops from Andariel (Echo of Andariel).
Unique power
Mobility Skills are always Shadow Imbued with [45 - 60]% increased potency. Lucky Hit: Damaging an Elite or Boss with a Mobility Skill has up to a [45 - 60]% chance to instantly trigger a free Shadow Imbuement explosion.
Affixes
Ranks to Shadow Imbuement (+1-3)
Where it drops
Echo of Andariel (Hanged Man's Hall, Kehjistan) - Greater Lair Boss, 2x Mythic drop rate (boosted/targeted drop)
Belial, Lord of Lies (Palace of the Deceiver, Kehjistan) - mimics any chosen boss loot table, guaranteed Ancestral Unique, highest Mythic chance