This is my go to Doomsday build. I try to bring up my HP and move speed first but I do like to get an early Lobo's Chain for the slow. Once I have that I get the Spear of Destiny to take advantage of the HP boost I got from Batmans Utility Belt, the Chain and the Amulet of Isis and then work on defensive items like the Fragment of Mogo and the Mirror Masters Prism. I use the Amulet of Isis to chase down enemy champions or to run from them. I try to use that in conjuction with Flash's Super Speed stolen power for maximum Rock and Roll. Doomsday's Charge (E) is, in my humble opinion, is his best move if used right. If used to push a champion into a wall, it will make it easier for your teammates to prioritize and finish off that champion if you haven't already and it makes your Stomp (Q) more likely to hit. You get added damage for rushing champions into cars and it's so much more satisfying with the explosion. The Berserk (W) ability doesn't reduce the cooldown with more points placed into it and it doen't bring up your move speed so I save that one for last, although I will get a single point in it ASAP to spam the extra move speed.  With all of those extra hitpoints and attack/power armor, Doomsdays Kryptonian Rage (R) becomes almost unstopable, even in a turret.