Legendary Difficulty same as Thunderstorm Skull?

Question

I'm trying to understand the difference between Legendary difficulty and using the Thunderstorm skull modifier in Halo 4.

From O.M.F.G.:

The Thunderstorm Skull is a doozy. It promotes all enemies to the highest available level, making combat much harder.

I'm not sure I get what differs between this skull and the highest difficulty level.

Thanks in advance!

Answer 1

On Legendary, enemies in general are more damage resistant, more accurate, and more insidious with their AI. They can also kill you with fewer hits. You will also encounter "leveled up" enemies more often.

The Thunderstorm skull makes the "most difficult" enemy variants far more common. For instance, without it, you might encounter a single fuel-rod wielding Elite on a Legendary Spartan Op, but with it, you'll likely encounter several. Similarly, you'll find more of the highest class of Knight (who have integrated sniper cannons) and so forth.

In practical terms, playing on Legendary with the skull off, you can frequently isolate the really tough enemies and single them out to kill them fast. With Thunderstorm on, most/all of the enemies are the "tough ones."

Answer 2

Looking at the Halo Wikia article about legendary difficulty, you can see that in all the previous games there have been effects beyond the scope of enemy level. In Halo 3 the players shield would be lowered, allies would be weaker and there seem to be more enemies. In Halo 3 the Thunderstorm Skull would improve allies as well as enemies, which is not the case with just playing on legendary difficulty.

In addition, it states that the Thunderstorm skull stacked with the legendary difficulty in Halo 3 so I would assume that it does the same for Halo 4.