Hard Edge style pixel art. There is no specific trigger word, just use "pixel art" or "pixel art style".

Should scale down perfectly by downscaling 4X with nearest neighbor.

Check out my other model, Soft Pixel Art, if you prefer a softer, more detailed style:

Soft Pixel Art - v1.0 | Stable Diffusion LoRA | Civitai

Tip: Combine both of these LoRAs at 0.5 and 0.5 to get an in-between look!