Planet at War is played on a different scale than classic picture wars, often abbreviated by ppw. Planetary picture wars uses very large spacecraft for ship to ship battles, at a small scale. At this scale, players engage in large scale space battles, and create large metropolis on the planet surface below.
Like any picture wars match, planetary picture wars armies and fleets can be any variety of things, from Terran battleships, to fleshy-alien ships and more. There is no official scale for making planetary picture wars armies, so players are encouraged to scale their fleets similar to other player fleets. At this scale, fighters rarely register as more than a few pixels, and battleship sizes are comparable to the size of infantry at normal picture wars scale.
Planet at war matches generally have no set goal, and play out like sandbox matches on a PPW scale. Players make their own cities, build up fleets, and attack each other at will. These matches can extend for dozens of pages.