~Don't use full screen, it can be very laggy, it depends on your computer. ~Use the right and left arrow keys to hover over an action. Use "Z" to select and "X" to back out. ~When attacking, press the "Z" key to attack. Hitting yellow does 5 damage, orange does 10, and red does 15. ~"Red" has 200 HP. ~Use the arrow keys to move. ~Use your items to heal. ~Press "1" to show and hide the health bar at the top of the screen. ~You can only FIGHT.
Credit to "Toby Fox - Undertale Creator" and to "Taxiderby - Undertale Red Creator"