Complex sentence: Due to Stane's life off the grid, Iron Man fails to realize who he is, and despite Tony Stark's resources as Director of S.H.I.E.L.D., Stane leaves California and prepares for the next stage in his vendetta against Stark.
Split into simpler sentences: Due to Stane's life off the grid, Iron Man fails to realize who he actually is. Despite Tony Stark's resources as Director of S.H.I.E.L.D., Stane leaves California and prepares for the next stage in his vendetta against Stark.