Ernie's Sabercane is a Lightsaber that constructed by Ernie to replace his old ones and Darksaber that were destroyed in The Battle of Night Fury Topia, after becoming an outcast.
Just after Ernie was given new arms, he went to find himself some parts to build a new Lightsaber for himself when he came across some broken bits of one, he then used the parts he found to build himself a new saber. And then he made a wood stick that he could detach on the bottom of it to pose as a cane (due to the fact that he now had a limp on his left leg).
Ernie then first used this lightsaber against Nightmare Inquisitors: Katty Katswell, Daphne Blake, and Brandy Harrington. And then he used it to kill 3 Skullcrushers. But then after revealing his true colors, he then used his saber to cut off Blackie's left arm. As he caused Pain to Sharon but then Blackie got back up. As Ernie went to strike him down. However, despite being down by one arm, Blackie stood his ground and knocked Ernie off the ledge.
Then in "Lost City of Opar" Ernie used this Lightsaber against, Jane Porter (who at that time was Queen La's padawan and escaped during the battle of Opar) using her lightsaber and Ernie used his, he has won the battle.
Ernie would later use this lightsaber against The Eeveelutions, till the final clash was struck when Umbreon bisects Ernie's lightsaber and inflicts a fatal wound to his chest. As he dies, he asks the Eeveelutions if the Chosen One is Breon. And they say "Yes". And Ernie says that he'll avenge them and he dies, and Eevee shuts his eyes.
The lightsaber produced a crimson-red blade, and the upper grip-guard resembled that of the Inquisitors' lightsabers, albeit broken and bent outward. He would hide the hilt by attaching a piece of wood to it, and pretending it was a walking stick, all the while masquerading as a feeble old man. It is likely that Ernie used parts of Dawn Bellwether's Old Lightsaber to construct this one, when it was destroyed at the hands of Sunset Shimmer.