Benefits of leveling up?

Generally I go around after completing a level and buy everything I can, even if it's just that random question mark and it ends up being the same active item that I already have equipped.

So I often wonder how much leveling up benefits you. I know you start with 12 damage and it goes up by 3 each level, but that's about all I know...

So anyone want to help enlighten me
Sorry if it's already been asked somewhere and I'm just blind ._.

 

Health of character increases as well. Then all items that deal any sort of damage depends on your attack. When you level-up, your items level-up also.

 

Okay, awesome. Thanks.

I misunderstood and thought you meant your items level up when you do lol. But only when you get them do they level up.

 

The itens do damage acording to your damage, for an example :
At lvl 10 (45 atk) you get the disposable rockets (or the item that alows you to randomly shoot rokets)
Every single rocket does 500% dmg, so you would do 225-203 dmg with it
Panic mines, gasoline, sacrificial dagger, fire shield, most of actives, etc are based on that

 

Oh? So rockets gained at level 5 are more useful than rockets gained at level 1? Interesting.

 

Items do damage based on a % of your attack, so they don't "level' per-say, rather; they scale AS you level. Getting rockets at level 10 makes them do (level 10 atk x 500%), same as if you got them at level 1 (level 1 atk x 500%)