The Cascade is a yoyo, and is currently the most powerful yoyo available before Hardmode. It can be held out for 16 seconds before it returns, and upon striking an enemy, has a chance to inflict the On Fire! debuff.
The Cascade has a 0.25%, or 1/400, chance of being dropped by any enemy in The Underworld after Skeletron has been defeated. Once Hardmode begins, it will no longer drop, as the stronger Hel-Fire will drop instead.
Its best Modifier is Godly.