Helped my little brother design a simple Lego hidden blade due to our shared love for the Assassins Creed franchise. It's relatively simple and not at all lore accurate, but it's the
LEGO Hidden Blade - Assassin's Creed - YouTube
Download Lego Hidden Gemini Dual Blades Da Justin Holeman
BrickWarriors Lego Custom Accessories Hidden Blade (Black - sold by unit) La Petite Brique