How do I get the elixir for it? I've tried looking it up on google but that isn't giving me the information I want. Please help.

unfortunately there is no Bloodred Celinox Elixir available. You will need a (Bloodred Potion) to use on your Celinox to turn it into a bloodred one. It restocks at the Magic Box if you are lucky with restocking one, but it is very rare ;)