feat: Add screenshot to README

README.md

@@ -1,7 +1,17 @@
 # Insta Kill
 
+A fast paced arcade like 2D game where everything dies in one hit, both the enemies as well as the player.
+You can play the game [in your web browser over on itch](https://praxtube.itch.io/magus-parvus)!
+
+<p align="center">
+    <img src="docs/demo/screenshot.jpg" alt="screenshot" />
+</p>
+
 ## Appendix
 
-[Credits](https://github.com/PraxTube/magus-parvus/blob/master/CREDITS.md).
+[Online Leaderboard](https://rancic.org/games/insta-kill/)
+
+[Credits](https://github.com/PraxTube/magus-parvus/blob/master/CREDITS.md)
+
 [License](https://github.com/PraxTube/magus-parvus/blob/master/LICENSE),
 applies to everything that doesn't already have a license.