HTMLify

		<canvas id="gc" width="600" height="600"></canvas>
<script>
window.onload=function() {
	canv=document.getElementById("gc");
	ctx=canv.getContext("2d");
	document.addEventListener("keydown",keyPush);
	setInterval(game,1000/10);
	setInterval(superblocks,2000);
	setInterval(obstaclemove,4550);
}
px=py=13;
gs=20;
tc=30;
ax=Math.floor(Math.random()*tc);
ay=Math.floor(Math.random()*tc);
apx=Math.floor(Math.random()*tc);
apy=Math.floor(Math.random()*tc);
porx=Math.floor(Math.random()*tc);
pory=Math.floor(Math.random()*tc);
sx=Math.floor(Math.random()*tc);
sy=Math.floor(Math.random()*tc);
ox=Math.floor(Math.random()*tc);
oy=Math.floor(Math.random()*tc);
obx=Math.floor(Math.random()*tc);
oby=Math.floor(Math.random()*tc);
obsx=Math.floor(Math.random()*tc);
obsy=Math.floor(Math.random()*tc);
obstx=Math.floor(Math.random()*tc);
obsty=Math.floor(Math.random()*tc);
score=0;
highscore=0;
scoreten=false;
xv=yv=0;
trail=[];
tail = 4;
function game() {
	px+=xv;
	py+=yv;
	if(px<0) {
		tail = 4;
		xv=0;yv=0;
		px=13;py=13;
		if(score>highscore) {
			highscore=score;
		}
	}
	if(px>tc-1) {
		tail = 4;
		xv=0;yv=0;
		px=13;py=13;
		if(score>highscore) {
			highscore=score;
		}
	}
	if(py<0) {
		tail = 4;
		xv=0;yv=0;
		px=13;py=13;
		if(score>highscore) {
			highscore=score;
		}
	}
	if(py>tc-1) {
		tail = 4;
		xv=0;yv=0;
		px=13;py=13;
		if(score>highscore) {
			highscore=score;
		}
	}

	document.getElementById("score").innerHTML ="Score: " + score;
	document.getElementById("score").style.font = "bold 25px arial";

	document.getElementById("highscore").innerHTML ="Highscore: " + highscore;
	document.getElementById("highscore").style.font = "bold 20px arial";

	ctx.fillStyle="green";
	ctx.fillRect(0,0,canv.width,canv.height);

	ctx.fillStyle="lime";
	for(var i=0;i<trail.length;i++) {
		ctx.fillRect(trail[i].x*gs,trail[i].y*gs,gs-2,gs-2);
		if(trail[i].x==px && trail[i].y==py) {
			tail = 4;
			xv=0;yv=0;
			px=13;py=13;
			if(score>highscore) {
				highscore=score;
			}
		}
	}
	trail.push({x:px,y:py});
	while(trail.length>tail) {
	trail.shift();
	}
	if(ax==px && ay==py) {
		tail++;
		score++;
		ax=Math.floor(Math.random()*tc);
		ay=Math.floor(Math.random()*tc);
	}
	if(apx==px && apy==py) {
		tail++;
		score++;
		apx=Math.floor(Math.random()*tc);
		apy=Math.floor(Math.random()*tc);
	}
	ctx.fillStyle="red";
	ctx.fillRect(ax*gs,ay*gs,gs-2,gs-2);

	ctx.fillStyle="red";
	ctx.fillRect(apx*gs,apy*gs,gs-2,gs-2);

	if (px==porx && py==pory) {
		px=Math.floor(Math.random()*tc);
		py=Math.floor(Math.random()*tc);
		porx=Math.floor(Math.random()*tc);
		pory=Math.floor(Math.random()*tc);
	}

	ctx.fillStyle="white";
	ctx.fillRect(porx*gs,pory*gs,gs-2,gs-2);

	ctx.fillStyle="darkslategray";
	ctx.fillRect(ox*gs,oy*gs,gs-2,gs-2);

	ctx.fillStyle="darkslategray";
	ctx.fillRect(obx*gs,oby*gs,gs-2,gs-2);

	ctx.fillStyle="darkslategray";
	ctx.fillRect(obstx*gs,obsty*gs,gs-2,gs-2);

	ctx.fillStyle="darkslategray";
	ctx.fillRect(obsx*gs,obsy*gs,gs-2,gs-2);

	ctx.fillStyle="gold";
	ctx.fillRect(sx*gs,sy*gs,gs-2,gs-2);

	if(px==sx && py==sy) {
		tail++;
		tail++;
		score++;
		score++;
		sx=Math.floor(Math.random()*tc);
		sy=Math.floor(Math.random()*tc);
	}

	if(px==ox && py==oy) {
		tail = 4;
		xv=0;yv=0;
		px=py=13;
		if(score>highscore) {
			highscore=score;
		}
	}
	if(px==obsx && py==obsy) {
		tail = 4;
		xv=0;yv=0;
		px=py=13;
		if(score>highscore) {
			highscore=score;
		}
	}
	if(px==obx && py==oby) {
		tail = 4;
		xv=0;yv=0;
		px=py=13;
		if(score>highscore) {
			highscore=score;
		}
	}
	if(px==obstx && py==obsty) {
		tail = 4;
		xv=0;yv=0;
		px=py=13;
		if(score>highscore) {
			highscore=score;
		}
	}

	document.getElementById("credits").innerHTML ="Programmed by: Dario Casciato";
	document.getElementById("credits").style.font = "10px arial"

}
function keyPush(evt) {
	switch(evt.keyCode) {
		case 37:
			if(xv==0 && yv==0) {
				score=0;
			}
			xv=-1;yv=0;
			break;
		case 38:
			if(xv==0 && yv==0) {
				score=0;
			}
			xv=0;yv=-1;
			break;
		case 39:
			if(xv==0 && yv==0) {
				score=0;
			}
			xv=1;yv=0;
			break;
		case 40:
			if(xv==0 && yv==0) {
				score=0;
			}
			xv=0;yv=1;
			break;
		case 65:
			tail++;
			score++;
			break;
	}
}
function superblocks() {

	sx=Math.floor(Math.random()*tc);
	sy=Math.floor(Math.random()*tc);

}
function obstaclemove() {
	obstchoice=Math.floor(Math.random() * 4);
	obstachoice=obstchoice=Math.floor(Math.random() * 4);
	if(obstchoice==0) {
		if(obstachoice==0) {
			ox++;
		}
		if(obstachoice==1) {
			ox--;
		}
		if(obstachoice==2) {
			oy++;
		}
		if(obstachoice==3) {
			oy--;
		}
	}
	if(obstchoice==1) {
		if(obstachoice==0) {
			obx++;
		}
		if(obstachoice==1) {
			obx--;
		}
		if(obstachoice==2) {
			oby++;
		}
		if(obstachoice==3) {
			oby--;
		}
	}
	if(obstchoice==2) {
		if(obstachoice==0) {
			obsx++;
		}
		if(obstachoice==1) {
			obsx--;
		}
		if(obstachoice==2) {
			obsy++;
		}
		if(obstachoice==3) {
			obsy--;
		}
	}
	if(obstchoice==3) {
		if(obstachoice==0) {
			obstx++;
		}
		if(obstachoice==1) {
			obstx--;
		}
		if(obstachoice==2) {
			obsty++;
		}
		if(obstachoice==3) {
			obsty--;
		}
	}

}
</script>
<p id="score"></p>
<p id="highscore"></p>
<p id="credits"></p>