We're talking purely about Spartans in MJOLNIR Mark IV. That variant did not possess energy shields. While it was [b]WAY[/b] more durable than your standard Marine BDU, it still couldn't take direct hits from plasma-based weaponry. If it weren't for the Spartans having a ridiculously high pain tolerance, MJOLNIR Mark IV users would likely either fall unconscious from pain or die from shock caused by a single direct hit from a plasma discharge. All of the examples you provided were of Spartans wearing later MJOLNIR variants that possessed energy shields and had been modified to better withstand plasma-based weaponry. And your final comment about the Chief's assassination of Regret is just really bad. Chief was utilizing MJOLNIR Mark VI, along with an onboard "smart" AI, and possessed far more experience with Covenant tactics than Red Team would have had only 6 years into the war. Also, you've said it yourself. Gameplay =/= Canon. Look, I don't deny that Spartans were far superior to any normal human soldier. But for a team of only three of them in Mark IV armor to survive against a massive number of Sangheili soldiers using melee weapons in a small area that early into the war is nothing short of complete bullshit.