Just a little tip on the blurred titles:
Munchkin: a very small person, or alternatively, someone who gets enjoyment out of ruining everyone else's fun. Someone who specifically decides to play characters that won't work with the rest of the party. Examples: someone designed to outshine the rest, someone designed to hinder the rest by being too weak, someone with in-character reasons to not get along with the party.
Power Gamer: Someone who likes powerful characters. They don't even necessarily want their characters to be more powerful than the rest of the party, nor do they want to stomp all over the opposition. This kind of person (me!) likes games that start higher than levels 1-3, because in the slightly higher levels, you're dealing with actual heroes. You're also facing monsters that you can actually write home about. One can of course be both a Power Gamer AND a Munchkin, in which case 99% of the time they want to outshine the rest of the party.
Optimiser: Someone who simply likes to play with the numbers, and likes to make their character the best they can be. They enjoy looking at the stats and playing around within the rules. They're probably happy to help other party members with their stats too, to make sure everyone is on the same footing. I sort of fit into this category, to a degree. I can still curb it easily enough though, as many do. Heck, a responsible optimiser knows that sometimes they SHOULD take something less than the best, just so they don't crush everything else (a Cleric who wears Light armour is a small yet significant change, as is playing a Sorcerer instead of the almighty Wizard).
Just being helpful here! Also covering my own ass to avoid "BAAAAAAW, kongming is a rollplayer, not a roleplayer!" Although people here probably know that's not true.
And regarding the troll: They're hard to make playable. Mostly because, if you don't go into "the land of acid, fire, poison and death effects" they're sort of unkillable. As a monster, it turns into a puzzle - the "How do we kill it?" puzzle as everyone whips out their acid flasks and fire spells. As a PC, it forces any meaningful challenge to have the answer to the puzzle.
Just being helpfully irritating as always ^^