The Answers for Wordscapes Level 50399 from the Strato 16 pack and Master group are: clone, con, cone, echelon, echo, eel, heel, hen, hence, hoe, hole, hone, leech, lone, noel, and once.
Just a heads-up: the puzzle layout on Master levels is autogenerated, so the grid you see here might look a little different than the one in your game.