How do I solve 22 down in Times Cryptic 5218?

Question

Accepted Answer

22 down reads "One with wind steps out of line" (5 letters); the answer is ADDER. It's a deletion clue: start with a word the clue points to, then drop one or more letters. Indicators include 'endlessly' (lose the last letter), 'beheaded' (lose the first), or 'heartlessly' (lose the middle). The full step-by-step breakdown is on this page.

One with wind steps out of line (5)

22D — One with wind steps out of line (5) — ADDER