What is the word to level 383 on 4 pics one word for the iPhone?

The first picture is of a girl doing a chemistry experiment, another is of a rainy scene with a radioactive planet in the back or some factory, another other is a group of people celebrating and throwing papers and the last one is of bug bites or some bumps on someone's skin. The letters are e s c a o t r k n e i

Strike

It's REACTION