You can see Kaiba there, crushed by the horse. Kaiba's name is written as 海馬, which means "sea horse".
Yes, Kaiba is a horse! XD
I have no idea why Ranma is there, though. Since this manga is chinese, I'm guessing all the characters have different readings than their Japanese counterparts, all with the kanji for horse (馬) on them.
And is that a MLP pony there!?