in Dark Omen

Treeman is a huge monster-unit in DO. Its characteristics and traits are identical (or very close) to the characteristics mentioned in TT armybook. 
Despite the description in both DO and TT which states that Treeman can't wear armor it still has a special armor type which imbues its wearer with different traits like weakness to fire. Treeman also has 2 Armor rating which corresponds to 5+ unmodified save in TT from trait called "thick hide". Whether it is unmodified save in DO or not is unknown.
Treeman has 2H weapon in DO (according to WHedit)