Why The Ending of Crisis Core is Profound

The reason it has such a profound effect on people is cause, the character, Zack, goes from ambitious newbie to veteran soldier, to renegade. He effectively becomes the player's best friend throughout the game cause you wanna root for him. That he'll face all these adversities like he always has... But... As the end rolls up. He sets cloud down, he knows what's waiting for him, and so do you. You've equipped him with all the good gear, all the best weapons.

The cutscene plays, and shows the rows upon rows of Shinra soldiers armed to the teeth. There's no way out but to fight. And despite your healing and tenacity, wishing, hoping that there's an end to the countless numbers.... The DMW rolls through all the connections Zack made through the story between other characters... Each one vanishing as the battle drags on till... Fade to black, More gun fire, sword swings.... The screen fades back.

Three soldiers are left with a helicopter approaching. Its night now and the rain is pouring hard. You heal, and fight tooth and nail. you know you can't fight the impending fate... Finally. Zack goes down. The last connection he made, Aerith.  She asks Zack if she'll see him again before simply saying, "I'll be here." Harkening back to the letters that were kept from Zack for four whole years. The soldiers fire more into Zack as the screen fades.

Zack lays there, in the rain in a pool of his own own blood. Cloud crawls over who is later entrusted with Zack's hopes and dreams, his living legacy as he hands over the buster sword his dying mentor gave him. We say goodbye to not only a well written character but someone who was a friend and a comrade in arms.

You're left a wrecked ball of emotions.

Grief for a fallen friend.

Sadness for Cloud who has lost effectively his only comrade and surrogate brother

Relief in that Zack doesn't have to fight anymore

Anger over Shinra and its means of operations that led to this.

Empathy for the cross Cloud now bears.

Pain in knowing that Aerith will never know what happened to Zack.

Everything comes crashing down and you can only cry.