Who said tentacles are only good for swimming in a weird manner? The admiral has no issues whatsoever with manouvering ground based obstacles. Swiggins can also perform a hovering technique by propelling himself upward with ink squirts. Quite splendid.
Swiggins launches himself upwards, which can be followed by an ink gliding move that lasts up to a few seconds, enabling him to slowly descend for a while instead of just falling down. While gliding, Swiggins can freely use Anchor Swing/Ink Spray, Anchor Hook, or Drop Anchor.