Despite its ridiculously high attack strength (which is fake), the real power of Shonk is its life to cost ratio. Shonk is a walking wall, and at the time of this writing (version 1.57) it has the highest life to magic ratio in the game for a unit. The real use of Shonk is to be a protector of the Tundra Orcs' advance, blocking key spots, being a gate or a flank blocker, allowing Grognack and / or Smashers to advance.
Its attack still can’t be ignored though, being more than functional to deal with many threats.