I want to try having designated 'beastmaster' military dwarves who train war animals and as a result are followed by a cloud of angry claws and teeth. However, I'm not sure what would be the best choice. What war animals do you use and why? Currently I've thought of:
Tigers (size 225,000): Quick, fairly decent size, can do a lot of damage with their teeth. Tigers probably have less fat on them than, say, a bear, so they might be harmed more by cutting attacks. Breed fairly quickly and aren't too expensive.
Other big cats (lion, jaguar, cougar, etc) (size 200,000 and lower): Seem to be smaller versions of tigers-- not sure if there are differences besides that.
Bears (size 200,000 grizzly, 400,000 polar): Slower, most likely fatter than the big cats. Do they resist damage more easily than more agile cats, maybe? Quite expensive compared to some of the other animals.
Dogs (size 30,000): Breed extremely quickly, very cheap. Unfortunately, they get killed very easily due to their size.
Elephants and rhinoceros (size 5,000,000 and 3,000,000 respectively): Absolutely gigantic and most likely able to stomp a goblin to pieces very easily. Assuming you've modded the raws so they graze at a maintainable rate, they might be decent beasts of war. Problems include slow breeding and maturing, and inability to store easily due to grazing. [Do rhinos have armor?]