Battle takes place on a planet warped by TOAA, the planet cannot be destroyed. The planet is mostly sky scrapers with lots of weapons over head. Weapons include replusors, ion cannons, and highest grade military firepower. The planet is roughly the size of Earth's Moon.
Stark only has access to the weapons while wearing the Bleeding Edge, or Extremis. Only the military firepower has ammunition, and it runs out after 20 minutes of constant fire. The repulsors and Ions need time to recharge after 1 hour of exhausted fire. (During Tony's 1 hour prep, do the weapons get re-armed)
Tony has access to every armor he's ever worn, or infiltrated. This includes Zeran the Tester armor, but he only uses it if he absolutely has to. Tony does not get any of the infinity gems he's had, or any outside tech. Only tech and weapons from armors he's had worn.
He gets 5 days prep prior to the first battle. After that, he only get 1 hour prep between each battle. TOAA gave him footage of each opponent, each file contains knowledge on the character, their strengths, and weaknesses. Tony cannot create new tech, he only can use what he has previously in every armor. He can piece together other OLD armors, but he cannot add onto the Extremis, Bleeding edge, fear itself, thorbuster, or Zeran's armor. He cannot take magic elements from the Thorbuster, or fear itself armor. Tony can wear the Bleeding Edge (or another old pieced together armor that would logically FIT) under the Thorbuster, but in the BE only can Tony use the weapons around him, once and IF Thorbuster is defeated. Zeran's power cannot be altered, or changed, if he's in that armor, he gets what he got from that Arc, which if my memory is anything was the whole power of the negative zone, plus some celestial power.
Round 1.) Red Hulk (morals off)
Round 2.) Beta Ray Bill (enraged morals on)
Round 3.) Magog (KC) (morals off)
Round 4.) Wally West Flash (morals on)
Round 5.) Superman (New 52) (enraged, morals on)
Round 6.) WB Hulk
Round 7.) Thanos (No IG, Thanos is his incarnation when Drax killed him.)
Tony is only bloodlusted, and morals completely off during 6 and 7. 6 and 7 can be won via K/O, BFR, Death.
1-5 - K/O or Death if absolutely necessary (we've seen Stark do this in the past with villains)