Bubble Chaos: a complete flash game in only 131 lines

game_playing = 0;
shot_sound = new Sound();
shot_sound.attachSound("shoot_sound");
pop_sound = new Sound();
pop_sound.attachSound("ppop_sound");
title_screen();
function title_screen() {
	attachMovie("main_menu", "main_menu", 1);
	if (_root.plname) {
		main_menu.player_name.text = _root.plname;
	}
	main_menu.play_button.onPress = function() {
		_root.plname = main_menu.player_name.text;
		removeMovieClip(main_menu);
		game_init();
	};
}
function game_init() {
	game_playing = 1;
	level = 1;
	game_over = 0;
	firing = 0;
	score = 0;
	Mouse.hide();
	_root.createEmptyMovieClip("game_scene", 1);
	game_scene.attachMovie("back", "back", 2);
	game_scene.attachMovie("hero", "hero", 3, {_y:400});
	game_scene.hero.onEnterFrame = function() {
		(_xmouse<40) ? this._x=40 : (_xmouse>460) ? this._x=460 : this._x=_xmouse;
		if (slow_enemy>1) {
			slow_enemy -= 0.1;
		}
	};
	game_scene.attachMovie("crosshair", "crosshair", 4);
	game_scene.crosshair.onEnterFrame = function() {
		this._x = game_scene.hero._x;
		this._y = _ymouse;
	};
	game_scene.attachMovie("points", "points", 10003);
	game_scene.points.my_score.text = 0;
	enterlevel(1);
}
function enterlevel() {
	combo = 0;
	kills = 0;
	slow_enemy = 1;
	for (x=1; x<=_root.level+2; x++) {
		enemy = game_scene.attachMovie("alien", "alien_"+game_scene.getNextHighestDepth(), game_scene.getNextHighestDepth(), {_x:50+Math.random()*400, _y:50+Math.random()*200});
		enemy.enemynum.text = x;
		enemy.points = x;
		dir = Math.random()*360;
		enemy.speedx = Math.cos(dir*Math.PI/180)*x/2;
		enemy.speedy = Math.sin(dir*Math.PI/180)*x/2;
		enemy.onEnterFrame = function() {
			this._x += (this.speedx/slow_enemy);
			this._y += (this.speedy/slow_enemy);
			if (((this._x-25<0) and (this.speedx<0)) or ((this._x+25>500) and (this.speedx>0))) {
				this.speedx *= -1;
			}
			if (((this._y-25<0) and (this.speedy<0)) or ((this._y+25>400) and (this.speedy>0))) {
				this.speedy *= -1;
			}
			dist_x = this._x-_root.game_scene.hero._x;
			dist_y = this._y-_root.game_scene.hero._y;
			abs_dist = Math.sqrt(dist_x*dist_x+dist_y*dist_y);
			if (abs_dist<65) {
				pop_sound.start();
				removeMovieClip(this);
				removeMovieClip(game_scene.crosshair);
				removeMovieClip(game_scene.hero);
				Mouse.show();
				game_over = 1;
				game_scene.attachMovie("play_again", "play_again", game_scene.getNextHighestDepth());
				game_scene.play_again._x = 250;
				game_scene.play_again._y = 300;
				game_scene.play_again.onRelease = function() {
					removeMovieClip(game_scene);
					title_screen();
				};
			}
			bullet_dist_x = this._x-game_scene.fire._x;
			bullet_dist_y = this._y-game_scene.fire._y;
			bullet_abs_dist = Math.sqrt(bullet_dist_x*bullet_dist_x+bullet_dist_y*bullet_dist_y);
			if (bullet_abs_dist<28) {
				if (this.points == combo) {
					combo_bonus += this.points*100;
				} else {
					combo_bonus = 0;
				}
				combo = this.points+1;
				height_bonus = (this.points*100)*(Math.ceil((400-this._y)/40)-1);
				score += ((this.points*100)+height_bonus+combo_bonus);
				game_scene.points.my_score.text = score;
				earned = game_scene.attachMovie("disp_score", "disp_score_"+game_scene.getNextHighestDepth(), game_scene.getNextHighestDepth(), {_x:this._x, _y:this._y});
				earned.disp.text = "Bubble score: "+(this.points*100)+"\nHeight bonus: "+height_bonus+"\nCombo bonus: "+combo_bonus;
				earned.rem = 0;
				earned.onEnterFrame = function() {
					this._y -= 0.5;
					this.rem++;
					if (this.rem>100) {
						removeMovieClip(this);
					}
				};
				pop_sound.start();
				removeMovieClip(this);
				removeMovieClip(_root.game_scene.fire);
				firing = 0;
				kills++;
				slow_enemy = 3;
				if (kills == _root.level+2) {
					_root.level++;
					enterlevel(_root.level);
				}
			}
		};
	}
}
function onMouseDown() {
	if ((!firing) and (!game_over) and (game_playing)) {
		firing = 1;
		shot_sound.start();
		game_scene.attachMovie("fire", "fire", 1000, {_x:_xmouse, _y:357});
		game_scene.fire.onEnterFrame = function() {
			this._y -= 5;
			if (this._y<0) {
				removeMovieClip(this);
				firing = 0;
			}
		};
	}
}