If your only requirement is dealing with Inkwell Leviathan then Thornweald Archer may work. It has deathtouch and reach. Not good against DSC, Akroma or Progenitus but good against Hellkite Overlord and Inkwell Leviathan. Also you can clamp him away for +1 if you really need it.
Thornweald is good in the R/G beatz build...however, i'm still trying to put in Ohran Viper in my deck as i'm trying to maindeck Null Rod and i'm replacing Skullclamp with Ohran...
i'm suggesting Ohran Viper in the X-mas beatings as the beatings build acts more of a control deck than an aggro deck and i think Ohran is more suited in this build...