Only when it came closer to him, did Rama understand that there were actually Sea Demons and Deep Ones hiding in between the Serpent Tentacles. With their help, they were able to utilise the System to open up multiple dimensional portals and enable the quick redirection of the arrows right towards Kurma.
After which, the Demon Sea Octopus did not give any quarters as he quickly turned the Serpent Tentacles into more like a living spear at their tips. Meanwhile, the sides of those tentacles were cannons that the Deep Ones and Sea Demons were holding close to it and started to pilot them and shoot Rama indiscriminately.