It's also worth noting that gaining levels too early can actually be detrimental, as the number of HP you gain when leveling up is a function of your vitality, and increasing your vitality doesn't affect the HP you already have. Thus, you will have many more HP if you increase your vitality as much as you can before you gain too many levels.
Of course, as long as you're cheating with Pandora's Box, you could quite easily give yourself thousands of HP, superhuman stats, and invincible armor as well... but I wouldn't recommend it. It would take much of the fun out of the game.
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"I don't really care either way on either topic, but I feel the need to express my ambivalence to make others care about my lack of caring." - mrxak
"The amount of useless things I wrote is truly staggering." - andrew