Special Units are a unique type of units which can only be created when one Hero unit levels up to level 4. Here, depending on which Faction he is owned by, he/she "invents" a new sort of unit or building that is superiour to all others of that unit type in the game. For instance, the Taslow tower is the most powerfull Defense structure in the game, though is a special building as it was made by Taslow when he was promoted to Rank 4.