nunu consume bonus damage

So i was goofing around on a nunu jungle game and i noticed that if the scuttle crab has been stunned it takes 25% additional damage from Nunu's Consume. The same interaction does not happen with Thresh's flay. other pictures below. First i thought it was only an interaction with Gift of heavy hands, but it also works with ranger's trailblazer smite.

https://gyazo.com/6f9e6356ab182065fd0ab870f79f4e8a https://gyazo.com/b66a476018d8bb018306e255278c4374 https://gyazo.com/2fa0eb487c4d1fade0f532b8dd16c992 https://gyazo.com/bfc495afaf8d42009cb178be286e7f28