S-M TAS [Spider Mutation]

Spider-Man The Animated Series - E20 [Enter Punisher]: Peter finds himself tangling with the Punisher who targets him believing him to be a threat to New York. At the time, Peter foolishly tried to use a serum to take away his spider powers only for it to mutate him, giving him four extra arms. The mutation flares up while he's running from the Punisher and soon reaches it's tip just as Peter is cornered.

Example of:
Transformation Discretion Shot