Sure, here's a basic implementation of the game you described using HTML and JavaScript:
To play the game, just save the above code into a `.html` file and open it in a web browser, preferably on a smartphone. The player can control the blue circle sprite using the arrow keys (up, down, left, right) to move, and the spacebar to shoot blue triangles in any direction. The goal is to eat all 100 moving black circles by colliding with them and shooting them with the triangles. As the player eats the black circles, they will grow bigger, and the triangles shot will also increase in size. The player's maximum size is 100. The score will be displayed on the screen, showing the number of black circles devoured.