The Spell Swap is a glitch in Dark Souls III in which the player is able to cast a spell even though the player does not meet the required stats for it, through the method of swapping to that specific spell "during the animation of another spell" in the Spell quick menu. The glitch is performed by pressing a series of buttons in sequence on either controller of keyboard to execute the glitch.
Patch 1.04 until Patch 1.14 until the glitch was patched in Patch 1.15Spell Swap Glitch Tutorial by AquaFR