So this was all Zangetsu trying to show Ichigo how to use bankai

Ichigo's Bankai, Tensa Zangetsu (天鎖斬月; Literally meaning “Heaven Chain Slaying Moon”), works by compressing all of his Reiatsu into one small condensed, By Bladegrip

Anime Bleach Ichigo Bankai Sword New Tensa Zangetsu Katana - COOLKATANA

Bleach: Just What Are Ichigo's Powers

Bleach Ichigo Zangetsu Sword Ichigo Bankai Sword Replica - Sword Blade Weapon Metal - Aliexpress

Zangetsu (Quincy Powers), Bleach Wiki

When does Ichigo get his Bankai? - Quora

Ichigo, Shin Tensa Zangetsu: Mugetsu by cicerondibuja on DeviantArt

Zangetsu (Zanpakutō spirit), Bleach Wiki

Bleach: 8 Bankai to be revealed in Thousand Year Blood War

Ichigo's New Bankai Look! – Bleach 475