Sure! Here's a simple HTML game where you can fight a bigger and stronger helicopter using custom attacks. It includes JavaScript code for the game logic and animations, and is enclosed within script tags. Please note that due to the limitations of this text-based platform, the code might not run as expected here. To play the game, copy the code into an HTML file and open it in a browser.
In the game, you control a robot at the bottom of the screen, and a helicopter attacks the city from the top. The helicopter gets bigger and stronger with each attack. You can choose your attack by typing it into the prompt when prompted. The game ends when either the helicopter's or your robot's health reach zero, or if the robot reaches a certain position indicating the destruction of the city.