Hi there…yes you can animate light intensity. You have a few options.
1. Animate your light power in Blender and keyframe accordingly.
Then you use a standard “play animation” puzzle to play the animated light intensity.
2. Alternatively…you could animate the light intensity parameter using the “set intensity to light” puzzle. You can either animate this through a variable or you could animate it based on a material value etc.
3. Depending on your needs and memory requirements you can bake your lights and shadows on your textures and uses an animated UV map to make the intensity change. Often times the overhead of additional textures is less than the cost of the redraws caused by physical lighting.
There are other light parameters you can animate using the above puzzles other than intensity as well but the processes will be the same.