Advantage

Same rules as regular 5e but for when you have 2 or move reason for you obtaining advantage you gain a +1 for every additional advantage you have over 1. Same applies for disadvantages.

e.g: If for instance you have 3 advantages and 1 disadvantage you end up with a regular roll and a +2, if for instance you have 4 advantages and 0 disadvantages you end up with an advantage roll and a +3, if for instance you have 0 advantages and 3 disadvantages you end up with a disadvantage roll and a -2.