When did ichigo learn heaven shocking lunar fang?

Ichigo Kurosaki learns the "Heaven Shocking Lunar Fang" technique during the "Bleach" series, specifically in the "Thousand-Year Blood War" arc. This technique is a manifestation of his Bankai abilities, showcasing his growth and mastery over his powers. The exact episode or chapter detailing this technique may vary, as it is part of his evolving combat skills throughout the series.