Since Alister wanted to be the strongest, he also had the ambition of being the jack of all trades, master of all.
It was also the reason why he didn't waste his Unparalleled Talent (Red) talent to study all of the knowledge and information available in the Zombie World. Because of that, he mastered most of the professions or jobs that the human race had developed.
In the world of Fantasia, not only was power such as mana and aura sought after, but artifacts were also one of the means to obtain power.
Although Alister didn't want to rely on external power since it wasn't as reliable as the power he had in his body, that didn't mean he wouldn't take advantage of having both internal and external power.
After all, being both a Grand Warrior and Master Mage plus wielding a powerful artifact, wouldn't that be the strongest strength possible?