The infinity stones each had a long and unique history. Some staying in the same place for millennia whilst others seemed to swap hands every few years. The most notable being the Space stone, the one that Steve first experienced and the one he had most (albeit still limited) knowledge on. Steve described his first encounter with the tesseract when he was battling the red skull and hydra.

"And what happened to the tesseract after that?" asked Rhodey.

"Bottom of the ocean. Fell out of the plane before I put it in the water"

"…yeah I've been meaning to ask, why did you have to crash the plane again?"

"There were bombs on board"

"…bombs on board… and you couldn't have jumped out of the plane before you crashed it?"

Steve's mind froze and muttered something about heroes sacrifice and the situation needing quick decisions before moving on. The tesseract had many owners from Red skull to SHIELD to Odin himself, all of whom it would be difficult to steal from. The best opportunity would likely be when the tesseract changes owners I.E Hydra to SHIELD or SHIELD to Odin.

Mid way through the mapping of the power stone, Clint came to a revelation.

"Wait, changing something from the past, that has no impact on the future right? Well if we're already taking something from the past to undo something in the future…" He looked at Steve who took a minute to catch on.

"No absolutely not-"

"What is he talking about?" questioned Natasha

"He's talking about taking a sample of super soldier serum from the past to undo what Thanos did to me"

"Ah I like the sound of that: Captain Steve Rogers, mighty once more. No longer weak and pathetic and… unworthy" proclaimed Thor, his last words trailing off

"Steve, didn't we all spend months looking for a suitable replacement. We looked at everything: genetic mutations, cosmic anomalies, even tried making our own enhancement formula.

"Natasha, that serum doesn't exactly have the best track record. People have been turned into unstable aggressive super soldiers or even just flat-out monsters"

"In my defence, I did get better"

"Sorry Bruce, I'm sure he didn't mean you-"

"Ha ha ha! I'm kidding! But Steve's right, that serum did turn me into a rage filled monster. But let's say we take one of Erskine's formulae from the 40s, we already know what the consequences will be."

"The Avengers break up for a third time?" Tony interjected sarcastically

"Steve we're already planning a time heist for the infinity stones, who cares if we take a little super serum along the way?"

"Look we only have enough Pym particles for one journey each so it's not like we can grab the serum and Tesseract in the same journey, unless you guys want to wait 3 years?"

"Honestly we don't even need the serum, if we could get a sample of your blood before Thanos, we could reverse engineer a perfect replica of Erskine's formula." Tony proposed

"How are you planning on getting a blood sample from me in my prime?" wondered Steve

"Ask nicely."

"Knock you out."

"Lie to you to get it."

"Get it when you're sleeping." replied his closest friends and colleagues

"Well, that was disturbing." murmured Steve

"Anyway!" interrupted Tony "I was thinking about getting it elsewhere. I know my dad was given a sample by the government after the war and he also owned the tesseract, there's gotta be some crossover."

"Look no, I appreciate all your suggestions but I'm not going to take any kind of enhancement formula again. I saw first-hand what happens when the super serum gets into the wrong hands which makes it my responsibility to make sure that never happens again and that means not making any effort to recreate it or take it from the past. Our priority should be getting the infinity stones, no detours. Besides it's not like I'm planning on doing any fighting soon, I'll be able to handle myself.

The others respected Steve's wishes and moved on to the other stones. Eventually Natasha pointed out that the Time Stone, Mind Stone and Space Stone were all in New York in 2012. The reality Stone was in Asgard in 2013 and the Space and soul stone were on their respective planets in 2014.

"All right. We have a plan. Six Stones, three teams. One shot."