You've never seen such a sight in your life.

Scientists transformed ordinary mice into fierce predators using a technique called Optogenetics, where they control neurons with light (blue light here)

When the light was OFF, the mice were calm, even avoiding prey

But with the blue light ON?

They aggressively attacked and even beheaded crickets & bit hard on toy prey.

If a beam of blue light can switch aggression on and off in a mammal,