Basic Trope: Murder and other Dirty Business gets easier to commit after the first time.
Straight: Dice, a new recruit, has difficulty making his first kill. After that, however, he gradually grows more comfortable as a soldier, slowly racking up quite the kill count.
Exaggerated: Dice is made an assassin against his will, and grapples with the notion of taking somebody's life just because he's been ordered to. Once he's made his first kill, however, those initial doubts vanish instantly, and his first reaction is to callously ask when he can do it again.
Downplayed: It gets easier for Dice to do his job, but it takes a long time.
Everytime you kill someone a part of you dies too
It's a war, and it's kill or be killed. If Dice lets his conscience bug him, he'll screw up and die.
Inverted: It Never Gets Any Easier; in fact, Dice is so sickened by his first murder that it gets harder for him to justify his actions and keep doing his job.
Subverted: Dice is told it gets easier each time, and tries to tell himself that. But even after his first murder, Dice continues to struggle with the nature of his work, even after the second, the third...
Double Subverted: His fourth victim, however, is such a monster that he's able to refocus, reassuring himself that all of his targets were Asshole Victims. This makes his future assignments much, much easier to complete.
Parodied: Dice goes from a simpering, quivering, knock-kneed kid to a musclebound jaded veteran with just a splash of blood and one Mook down.
Zig Zagged: After making his first kill, Dice seems to become more comfortable with killing for a living... however, this is just an act, as he struggles to hide his insecurities and vulnerabilities. Eventually, it appears that he's Become The Mask and honestly adjusted to it... but then a mission goes pear-shaped and he's revealed as a Broken Ace.
Averted: From the beginning, Dice has no problem with the idea of killing.
Lampshaded: "Ever noticed how, for some people, the more they kill, the less they're remorseful about it ?"
Invoked: Dice's superiors fling him into combat as soon as possible, counting on this to harden him up — assuming, of course, he doesn't die in the process.
Defied: Dice is a Hitman with a Heart who makes a point of learning the name of every man he kills, so he doesn't get too callous.
Deconstructed: The killing gets easier, as does justifying it, but Dice's personal life becomes more and more unstable as he continues to take lives. He becomes increasingly anti-social and emotionally distant, unable to form any long-lasting relationships because he's trained himself to remain detached in order to make the killing easier to reconcile.
Reconstructed: Dice is a professional soldier or policeman, and is able to separate his job from his personal life. Killing in the defense of others becomes almost second nature to him, but he doesn't goes Jumping Off the Slippery Slope and become a cold-hearted killer. He's a devoted husband and father, a positive figure in his community, and an all around decent person who will end you if you threaten the safety of those he has sworn to protect. He does struggle with stress, but his family and friends are there to help him through it.
Played For Laughs: "I could never harm any living th—AHH! A bug!" * SQUISH* "...Hey, that wasn't bad at all!" * SQUISH SQUISH SQUISH* "Hahahah! Tremble before my might, poor pitiful unaligned ants!"
At first I had my doubts. Those were innocent electrons, you know, and I had to kill them just to edit these tropes. I cried...at first. But you know what? It Gets Easier. See? Just click on It Gets Easier.