The kata 自然 Shizen is a natural response to an opponent's choke. Bujinkan gokui says 豹変して必ず勝つ hyohen-shite kanarazu katsu, "Sudden change will always prevail."
the kata 雲雀 Hibari, a type of skylark. The evasion is 潜型 moguri gata. Then you “flush” up with a sudden strike to catch a hold and drop him like a rock.
My Bujinkan video exploring 自然の流れ Shizen No Nagare. Hatsumi Sensei described this idea as a natural flow. He said, “You need to be able to live within nature and survive within nature. It doesn’t matter how many techniques you know.”