Is there any difference between Ceres summon unit and general unit? Cres summon unit is just shattered by Howl.
Ceres summoned unit and general unit are all same. Ceres has a special power of copying allies into spirits. Those units spawned by Ceres have 50% health and you can take their HP to 100% by healing. They can do all the things what a general unit do. Ceres has a howl effect as well ( less powerful than howl pal but) which increase speed of every unit ( copied units too )
You can find this in detail here