Imponence:
1. Ju Peter (the biggest of all; also can come from the ground, seems to be the most unpredictable);
2. Mars (the flying ability + the size makes it very menacing);
3. Warcury (seems to be the more beastly and is also quite big);
4. Nusjuro;
5. Saturn (seems to be the smallest).
Scariness:
1. Saturn (actually the one that would fit a horror movie the best, looks like a demon spawned from hell and has the most unique design of all too);
2. Ju Peter (could fit in a horror movie too, something like the classic franchise Tremors);
3. Nusjuro (a skeletal horse, could fit the horror theme too);
4. Warcury;
5. Mars (not really scary, more on the cool side).
Overall (my preferences):
1. Ju Peter;
2. Saturn;
3. Mars;
4. Nusjuro;
5. Warcury.