Sure! Here's an implementation of the game you described using HTML and JavaScript within a single HTML file:
To play the game, you can copy and paste the above code into a new HTML file, and then open that file in a web browser. The game will run, and you'll be able to control the blue circle with red eyes using the arrow keys on your keyboard. Press the spacebar to shoot red triangles in the direction of the mouse pointer. The goal is to devour all 200 black circles by colliding with them. The more circles you devour, the bigger your blue circle becomes (up to a maximum size of 100). If a black circle is larger than your blue circle, it will kill you on contact. The black circles will fade out after you devour them. The current score and the number of remaining black circles are displayed at the top-left of the game canvas.