The Sigma Operator is intended as a very powerful crowd control, merging all hit numbers into one single target to deal with.
The real problem is, how to incorporate 3 different weapon modes into it?
Mode 1 is simple, a lob AoE, easy to aim, useful in certain situations.
Sum Barrier is basically Mode 1, but stationary, but can absorb and sum numbers together over a longer time period.
Magnet Aura is probably the strongest mode, but in the end just a better, mobile, version of Sum Barrier.
So naturally Sum Barrier needed an upgrade and it got one :D
I've added 2 new upgrades to it and with them now numbers can be manipulated while they are trapped inside the barrier and if you are able to reduce the sum barrier to 0, you get SP (meta currency) equal to the amount of numbers absorbed with it. This positions the Sum Barrier as a tool for SP farming and stationary crowd control.
Problem Solved, on to the next one!