Asta never had any real hopes of victory against Lucius Zogratis. The evil antagonist hiding in the Magic Emperor Julius Novachrono anime has actually proven far superior to his anti-magic. But the protagonist of Black clover has found a new way to overcome its limitations.
As the guest of the Shogun from the Land of the Sun, Asta knows he is no match for the enemy threatening the Magic Kingdom. Despite this, he intends to return home to confront Lucius. To prevent him from making a serious mistake, Shogun Ryuya will invite him to do so train with his best men.
Like this, Asta finds out about Zetten, a special technique that allows you to catalyze your energies and release them like a clean cut. This power is so complex that only the seven Ryuzen, the strongest in the Land of the Sun, can use it. The first time, however, Asta learns the basics of the technique.
In Black Clover 340, Asta is invited to a friendly challenge with the Captain Yami's younger sister, Ichika Sukehiro. Despite Devil Union Mode, Asta can't match Ichika in any way, who instead has mastered the Zetten perfectly.
A resounding defeat makes Asta understand the key to winning the battle with Lucius it dodges his attacks, waits for the right moment and only then pierces his defenses with the decisive blow. It won't be that easy though, as life gets tough for Asta in Black Clover 341.