Let me sort this out for you kiddies, and trust me ok?
Ki Blast is a small ball attack that all characters have. It is not controllable. When you press left click, the character fires off ki blasts using one hand. If you press right click instead, the character fires off ki blasts ALTERNATING from each hand.
In other words, right clicking fires faster than left clicking. No, there is no power difference. The difference is that left clicking is more accurate.
When several ki blasts hit the same spot, they form the ki blob. It doesn't matter which click you use to power the ki blob, although right click will power it faster.