Pretty sure that was just a colloquial reference(albeit made in somewhat jest) to how 2 planet-busters fighting on a planet, will inevitably end up busting the planet.
Ironman vs Hulk...Ironman thinks Hulk is the strongest being on the planet. Not only that, Ironman hits Hulk with a city and Hulk is still coming. Is unfazed by it.
By the way, here is proof. Strange sent a crew in to free order, the other half of the In Betweener. They made it to the door and Read what is said "we made it to the door. Let's free the other half".
Used nearly all of his power to contain Hulk and Hulk was still getting stronger. In time, we all know what would have happened (this isn't even WWH or World Breaker, this is just Savage that expanded his power like that). This same guy was controlling an IG user and the Phoenix Force. Crazy fts for Hulk. Insane ft.
Here is where the In betweener said he regained most of his power after letting Hulk go...
Actually, all of those below were posted before. Some were in the first page if this thread. and sentry was unable to stop Blastaar because he was weakening from the Negative Zone radiation and anti-matter particles emitted from their bodies. Sentry's Weakness. The same reason he lost to Blue Marvel (partially) and Anti-Man.
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Thanks for the sig Scot-and for the help with my avatar
When someone annoys you, it takes 42 muscles to frown but only 4 to reach out and bchslap them upside down on their head