I’m as rusty as some of the others here in terms of my memory.
First 2 Star Champion
Was into 4* land when they introduced championing, so I guess it was all of them, really.
First 3 Star Unlocked (if you can remember)
IM40 (pre buff, when he sucked, but I was blown away by his blue AE which seemed really powerful to me at the time, even if it did cost 20 AP or something)
First 3 Star Champion
Similar answer to the first question, I guess. I might have champed Steve Rogers first out of nostalgia, since he was my first maxed 3 star, though.
First 4 Star Unlocked
Fury. There were only 3 4-stars when I started playing this game, IW, XFW, and Fury.
First 4 Star Champion
XFW, one week before they nerfed him, lol
First Five Star Unlocked
OML
First Five Star Champion
OML
First PvE Win (if none what was you highest finish)
Venom Heroic. This was before Heroics had subs, and scaling progressively got more and more horrible as the event went on, since it would ramp up more and more due to personal and community scaling. You’d end up being unable to beat half the nodes on the map. I think I won Beast for that event, and he was the worst 3* around at the time, although he was still a 3*, dammit, and it was his release event, so we all didn’t realise how badly he sucked until later.
Also, slightly off topic, but I was also one of those fools who actually finished Boss Rush, just because I wanted to prove a point. I’m still not quite sure what that point actually was.
First PvP Win (If None What was you highest finish)
Red Shift. I think I won a single Starlord cover for it (pre-SCLs), and this was pre-buff too. I seemed to have a track record of mostly winning the worst character in each tier, lol.