Naoto upstages Mitsuru at the Catherine-themed shooting gallery with her own shooting prowess by shooting one of the sheep figurines, leaving a tunnel where his heart would be — without looking straight ahead at the target!
Aigis then ups the ante by unloading on the entire gallery — not a single bullet misses.
The ending of this game gives the phrase "killing time" a whole new meaning. The cast effectively KILLS Chronos, the current embodiment of the human concept of time, allowing his human side, Zen, to pass on to afterlife with Rei and a new, less human-hating Chronos to be eventually (and hopefully) born. Oh, and did we mention that Chronos, additionally to being a force of nature, has power over human lifespans, something he is not afraid to make use of in his boss-fight? Trust me, this is one feat that will always feel impressive, even when you're playing on Easy Mode.
Yu and Makoto gaining their Ultimate Personas by being pushed into a life-or-death situation by Margaret definitely counts as this.