Depends a little on what you mean by without spending money. I got fulll stable upgrades and I run memberships, but all that does is to speed up the progress. I dont use auto heal or auto repair, which give a small benefit in regular area and BG. And now that purples can be bought with gold, everyone can have that aswell given time. Only thing that can be bought and give a huge advantage in the game play is a full set of achievements. I run most of my gladiators with only gold achievements and an example of success with only gold achievement is Minde, currently # 9 in Primus using 250hp and 100hp buffs.