Even without the ring, he may be able to devise a way to defeat Hal. With the yellow ring, and his intellect, he defeats one of my favorite characters.
Doom proved that he can MASTER ANY new weapon, technology or mysticism that he acquires.
MASTERS.
Whether it's power stolen from Galactus, Silver Surfer, Belasco or Mephisto.
Hal is a prodigy with the ring, one of a kind: arguably the greatest lantern of all time. There's no doubt Doom will have mastered the ring, however Hal is special.
That's why I'm saying Dooms intellect is overrated. Doom gets his ass kicked.
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Iboga chose not to fight, to allow himself to evolve. He had the wisdom to abandon the actions of war when he knew they would no longer serve him.
Doom would definitely out think Hal, and thus use the ring with unimagined versatility and creativity. he also does not lack for blunt, obstinate willpower.
the most likely scenario imo, is that Hal attempts to overpower Doom with some blunt attack while Doom makes some esoteric weapon from the ring and siphons Hal's ring's powers and then all the Oan energies in the DC universe...
Oh and that's Doom's emo, steal other guys power to provide a physical threat for guys well beyond his level. Well, having a sinestro ring won't stop him from getting pounded by Hal.
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Iboga chose not to fight, to allow himself to evolve. He had the wisdom to abandon the actions of war when he knew they would no longer serve him.
If ALL Doom had, was the ring, I stll think he would beat Hal.
But, it isn't all Doom has.
Get it? It just "icing".
Doom is already Gawd-awful dangerous, powerful and brilliant.
Then, he gets the ring.
Imagine Hal, with Doom's occult knowledge, technical mastery and sheer strategic brilliance.
And, are you kidding? Are you really going to paint Doom as lacking in will power?
This is the guy that defeated the Beyonder WHILE he was being dissected.
Doom's advantages:
- he's one of the most brilliant scientific/strategic geniuses: meaning he will do stuff with the ring that others never fathomed or dared to attempt
- no ethical considerations to hold him back on exploiting the ring's versatility
- fast learner
Hal's advantages:
- greater willpower
- more experience
Hal wins. But if Doom gets more time with the ring, outcome is less certain.