The Knight Energy Sword (also called a "Star Sword" or simply "Knight Sword") is the mystical weapon wielded by Mysticon Knight. Its original wielder was the unnamed original Mysticon Knight, a male dwarf, who had wielded a mystical broadsword in battle.
Now it is wielded by his dwarven female successor, Emerald Goldenbraid.
It can slice through practically almost anything, with the exception of solarite rock. An additional mystical weapon is later joined with it- the legendary Silver Trident, which is utilized only underwater, and was given to Emerald in Episode Fifteen.
- Enhanced Swordsmanship
- Enhanced Slashing & Slicing: It is strong enough to cut and slice through practically any solid material, with the exception of solarite.
- Mystic Energy Wave: It emits an unusually strong wave of pink glowing energy that can hit several victims at once from a short distance.
- Portal Creation: Just the mystic Dragon Mage Staff, it can open circular, magenta-colored sparkly portal to another world or dimension. This was seen in "The Foz Who Saved Lotus Night."
- In the French animated show of Code Lyoko and its cancelled live sequel Code Lyoko: Evolution, Ulrich Stern and William Dunbar are the only Lyoko Warriors who wield a bladed weapon- Ulrich with his sharp saber/katana, and William and his larger sword known as a "zeilwielander."