Use the Arrow Keys to move your Soul. The colors of the attacks do not mean anything, other than "That's the Soul Color of the Soul that's attacking you!" (Green Attacks don't heal you, they hurt you, Turquoise Attacks hurt you even if you stand still, Orange Attacks hurt you even if you move, and other colored attacks just hurt you, not do anything new.) If you survive all of the attacks, you will win (Duh!).
As it says above, thanks to SquashyLegend for the original project, "Undertale Human Souls Genocide Battle". I'll make another battle like this later today. (EDIT: I made it! Here's the better version! https://scratch.mit.edu/projects/328844550/) The Green Soul's attack moves 10 steps instead of 20. The Purple Soul's attack is WAY slower. Make it to one of the top corners! The Turquoise Soul's attack is the same... ...I think... ...I forgot. The Blue Soul shoots its... ...Blue Friendliness Pellets???? ...Anyway, it shoots them slower. The Orange Soul has a slower attack, and it disappears more quickly. Use the box teleporting you to the center to your advantage! The Yellow Soul's attack is WAY smaller, and it moves slower. The combined attack is almost exactly like The Orange Soul's attack, but it disappears immediately.