Possible example of a blue card for Magic: The Gathering: Battle of Wits. This enchantment causes an instant win during its controller's upkeep if said controller's library contains at least 200 cards. It's not as blatant as any of the other colors' cards, but still partakes of the same theme.

Is anyone else disturbed by the enthused tone of the comments in the Real Life section?

Regarding Nanoha examples, I'd say it isn't overkill if it's what it takes to do the job. Fate and Vita were just as powerful as Nanoha (and in both cases Nanoha lost her first battle with them), so she had to use everything she had if she wanted to defeat them.

Quattro is a possible example (a justified one, though - Nanoha wanted to knock her out now and here).

I'll give you another example: in Nanoha A's the original Reinforce used a city-sized Starlight Breaker against the heroes. (Due to its overly long casting time, the heroes had enough time to get away.)