>>35073028Long Reach ensures that a Pokemon can make a contact move without triggering any effects, abilities, or items that may activate upon contact.
Baneful Bunker won't poison. Beak Blast won't cause a burn. Spiky Shield reduces attacker's health by an eighth. King's Shield lowers attacker's attack stat by 2 stages.
Aftermath, Cute Charm, Effect Spore, Flame Body, Fluffy, Gooey, Iron Barbs, Mummy, Rough Skin, Static, and Tangling Hair won't activate. Rocky Helmet won't inflict damage to the user and Sticky Barb won't transfer to the user. IIRC it is the ability version of the Protective Pads.
Is this nichey? Yes, but it still has a good purpose and can prevent stupid situations such as Static or Flame Body paralyzing the user if they make contact. For physical sets, Decidueye can use Shadow Sneak, Brave Bird, Leaf Blade, Phantom Force, Sucker Punch, and Shadow Claw without issues. For special sets, Decidueye can use Grass Knot without issues.