You know what's an amusing thing about the previous two Eclipses? The way the both of them were with Sun.
They were never kind to him, no, it would be foolish to say that either the first Eclipse or the backup Eclipse were kind to Sun. But regardless of which one we're talking about, Eclipse has always been more, indulgent with him.
When Sun first met Eclipse eye to eye after that fateful argument he had with Moon in Beta-10, Eclipse was... weirdly gentle? It's not even the correct word for it, but he appeared to indulge Sun and his anxious rambling, before shooting him down. He was also much more friendly than he was with Moon, probably because he did not see Sun as a threat, but still. He quite helpfully pointed out the exit point to Sun, and was acting kinda peacful. He was also less antagonistic, although he was definitely condescending.
When Sun exited the mindscape, he apologised to Eclipse, and Eclipse replied something like: "Oh, don't be sorry, only time you're ever sorry is when it actually IS your fault." which is obviously a jab. However, there's also a hidden admitance, that Sun is innocent, and is not at fault. It kind of feels like comfort from Eclipse? This was preluded by Eclipse admiting that Sun WAS a good person, but with issues (like everyone else lol).
Also, ever since Eclipse locked Sun and Moon into the Infinite Staicase SCP, and forced Moon to admit that he (Eclipse) IS better, seemed to have put more weight on Sun's opinion. Which can be clearly seen in the episode where Sun, having been fed up with Eclipse constantly throwing him and New Moon into things, exploded on him, and Eclipse just... left.
He also passed up some opportunities to actually hurt him? Like we now know, that Sun was tortured in the mindscape, but the first interaction we see between them, which is not a power struggle, Eclipse never got violent. He was a jerk, but a toned down jerk compared to how he was with Moon. Eclipse also, during the first ever video fully focused on him "Sun and Moon TRANSFORM into ECLIPSE in VRCHAT", said he was going to kill Sun, and then never followed through with it, even though he had the entirety of October to do so. Like my guy, do you or do you NOT want to kill him? You said you wanted to! Then actually do it, pussy!
And Eclipse is a killcode right? They said in the show that he is so. But compared to other people, he's actually kinda peacful. Like there are only a couple confirmed kills Eclipse has, like the homeless person he beat to death using Monty's body and the government official before that.
All these can be said to be little things, that Eclipse did not bother with, because they seemed like a waste of his time, but there is one piece of information he had, that could have destroyed both his enemies from the very beginning. A neat little fact. Moon wanted to kill Sun. He wanted to kill him, because he felt injustice at the fact that he was locked into their mind, and wanted a body of his own. The fact that it was their PLAN to do so.
Of course it was probably an intrusive thought of Moon, corrupted by his homicide code, and was probably his greatest shame. Before Eclipse that is. And it's obviously understandable why Moon wasn't jumping at the chance to tell this to his brother, the ONLY person he could fully, truly and wholly love and care about (before Lunar also appeared), but then why didn't Eclipse?
He could have won. He could have won before the brothers had a chance to realise how screwed they actually were, before the October Takeover, before the Wither Storm, before the infamous Beta-10 argument, before anything really. All he had to do, was basically poison Sun with this hate, and ruin any sort of relationship Sun and Moon ever had. Sure, probably when he would have first told it to Sun, he would've thought him a liar, but doubt eventually would have come. That was something Moon could not have countered in any form, and he probably would not have wanted to from how terrible he must have felt about that. Moon would have probably given up, if confronted with that information, because I don't think he'd have lied about something of that magnitude.
But alas, Eclipse never told (probably cuz Reed and Davis had no solid idea about it back then). This could have been such a powerful trump card from him. He could have ruined New Moon and Sun's relationship before it even began! Because back then Sun was still (understandably) more attuned to the Old Moon. So he would not have overcome it as easily, not saying he would do so now. Eclipse could very easily break Sun's fragile little sanity. And yet he never did. He never once even uttered anything similiar to it when in front of Sun. Sure he threw insults and taunts, basically tortured the guy for funsies, but this was a line he never once crossed. And I'm not sure why.
Eclipse had a strong ace up his (non-existent) sleeve, that he could have used anytime. At all times, it would have allowed him to win. But he never once used it. He took it with him silently, everytime he was defeated. I can't stress this enough.
This man had the chance to destroy his enemies with just a couple little words.
But both times he took it to his GRAVE.
Let's see if this one will too (:
