Talk:Flowey/@comment-27298982-20160920101957/@comment-5956954-20160920102536

That's just the "evil all along" trope. Very common.

''Renji Abarai:It's not true... The Captain Aizen I knew... will never do such a thing...

Sosuke Aizen:"No longer the Aizen you know," hm...? I'm afraid you've been deluded, Abarai-kun...The 'Aizen Sousuke' you knew, never existed to begin with.''

— Bleach

''the hero is searching for a very special treasure. Too bad he doesn't know his way around. He meets a very nice person who offers to help the hero find the treasure. But wait, wasn't the temple supposed to be toward the south? Then why are you walking north? And why won't his guide answer his questions? And oh drat, there's the Big Bad. That "guide" was his minion, and thus evil all along.''

—TV Tropes

Etc.