Control your heart with the arrow keys. Use Z to use a command, X to cancel. In this Undertale battle test, your goal is to defeat Zayden. You can do so by killing them or sparing them. To kill Zayden, use the FIGHT command until they are dead. To spare Zayden, use the right ACT command until they are able to be spared and then use the MERCY command. There are a lot of cool things you can do in this engine, so be sure to experiment.
I TRIED TO EDIT THE TEXT BUT THERE IS SO MUCH GOD DAMN STUFF IN THERE I COULDENT FIND THE TEXT STUFF :(