According to the story line, only Dire horses and Ikrans and the occasional Toruk can be ridden by Na'vi. However, we see Neytiri getting on the Toruk with Jake. She doesn't make Tsahaylu with it but is still the seventh Na'vi known to have ridden one. But there should be songs and stories about her for generations because she is the only Palulukan Makto!. I didn't see her do it but in order for her to have ridden and controlled the Palulukan in the attack on Quaritch in his AMP suit she had to have made Tsahaylu with it. This in itself should be the stuff of legend for the Na'vi, and may portend a really amazing future for her in the coming sequels. I haven't seen the game yet. Has anyone seen any reference to any Tsahaylu between any Na'vi and any other animal? The Titanothere and the Hexapede (Yerik) seem to have pretty large neural queue's, the Sturmbeest appears to have a rudimentary one in some views. Interestingly the Palulukan must have a very rudimentary one, I haven't been able to pick it out specifically from the sensory quills. The Viper Wolf appears to have a very well-developed one, but it is a pack hunter and the Palulukan is solitary. May make a difference, but all Pandora animals are supposed to have them.