Rule the first - Always listen to Pepper
He should have listened to Pepper.
If he had, Tony would probably be holed up in his workshop right now, a slice of pizza in one hand, AC/DC blaring nice and loud and the plans for something ridiculously awesome underway. Instead, he's standing, in temperatures cold enough to make a polar bear weep, preparing to face off with Papa Smurf's homicidal giant of a brother.
"Sir," Jarvis starts, sounding a bit distorted. "I'm afraid I have to inform you that systems are currently operating at 5% capacity. All non-essential functions have been disabled."
Tony watches through the suit's visor as his opponent flexes a bicep the size of his waist. There is a low rumble of anticipation from the gathered crowd of blue, deadly-looking giants. Right at the back, Tony can just make out a cluster of individuals wearing SHEILD issued arctic gear. He takes some pleasure in the fact that they seemed pretty miserable too.
"So, repulsors-"
"All weapons are deemed non-essential. Internal heating is being lowered to ensure continued mobility."
Great. So now he got to be miserable, cold, and soon to be dead. "Don't know if you've noticed Jarv, but that guy over there looks like he wants to eat me. I think weapons are pretty essential, given the situation."
The only response he gets is a faint hiss and crackle. "…Jarvis?"
Damn. Apparently Jarvis wasn't essential either.
Before Tony can make any attempt to re-activate his trusty AI, a sudden hush falls over the crowd. Tony looks up to see a slender, refined figure walk out and take his place on a high, icy throne overlooking the combat ring. Blue, like the rest of them, but smaller, lithe and almost beautiful in a cold, deadly way. Tony feels himself shiver as red eyes fix upon him, seeming to stare right through the suit to Tony himself. It's not that he's unsettled, of course, just that it's starting to get really damn cold.
The crowd sinks to their knees in a show of deference, as does Tony's opponent. Tony wonders for a moment whether he should follow suit, but he's got the nasty suspicion that if he was to kneel he might not be able to get the suit back standing again anytime soon. Luckily, the figure on the throne (Loki, it must be) seems to find Tony's defiance amusing, albeit not amusing enough to spare him from fighting Big-and-Icy over there.
"You may rise." Loki announces, in smooth, cultured tones. He sounds on the verge of boredom, like he has to watch fights to the death every second day and he got over the novelty of it a long time ago. The Jotun rise to their feet, and Tony goes back to feeling ridiculously small.
To compensate, he adopts a fighting stance, trying to ignore the creaking of the suit as it fights against the ice that has formed in every crevice. He might not be giant-sized, or insanely muscular, or have even a working suit, but he's still Tony Fucking Stark, and he's not going down without one hell of a fight.
From his position on the icy throne, Loki leans forward slightly, a faint smile curling his lips. Somehow, he has the feeling that this fight might be of more interest than the usual petty squabbles. The mortal in the metal suit has not yet called for mercy, or forgiveness, as those that faced Hjálmgerðr were generally prone to. No, he seemed positively fearless in the fact of near certain defeat. Loki knew that Hjálmgerðr expected to win this fight, or the brute would not have issued the challenge, but Loki find himself not so sure. He calls out into the cool air, "Let the honour-match commence!" and settles back to watch the show.
Down below, Tony stands his ground as the huge form of his opponent races towards him, ice cracking underfoot. His mind races through calculations, dismissing one futile plan of attack after another and wishing that this wasn't happening.
Damn it, he should really have listened to Pepper.