Stacking auras?

is there ne way that u can make auras stack? I want to have items that when equiped add negative auras to yur attack speed, evasion rate, etc. but i also want the unit to naturally have a certain evasion rate and such... but that would pretty much need atleast 3 of every type of aura. (natural unit auras, weapons, armor, shields, other garbage)

so yea....is there newayz i can make em stack? thanks...