So I get some of it but its still confusing

a) Is the sideline part of your force?

b) If your starting team or sideline contains a prime, can the other contain a prime? (same for duplicate Unique figs)

c) You can't bring in game elements not legal in the event, but can you have them on your sideline anyway?

d) New Ant-man, his morph forms have to be sidelined, but what about the Ant bystanders he generates? Do i have to split my sideline between Ant-mans and the Ants he makes?

e) If so for (d), how does this affect characters that generate bystanders that you don't get pogs for (like lobo)?

f) when figures are ko'd, do the go to the sideline?

I know that the answer to (b) and (c) are definitely "no"

http://www.wizkidseventsystem.com/bb...&t=3714&p=8718
http://www.wizkidseventsystem.com/bb...t=6403&p=14058

Can't find the quote about Golden vs. Modern age but it is on here as well somewhere.

(f) is a "no" as well. From the 2014 Core Rulebook:

Zandig covered most of your answers so I'll try to catch the rest.

For all parts, they haven't said "officially" in so many words what exactly the sideline is so I'll be more generic in some of them to explain the concept behind it. Most of us are hoping there will be a good few paragraphs in the new rulebook to say what the sideline is and isn't.

a) They are part of your overall force that you bring to the event, but they are not part of your build (adding up total points on your team). As Zandig pointed out, Primes and Uniques on your sideline count towards (or against?) the limitations of each of those categories, but the sideline doesn't apply to themed team or anything that would be important to call them "part of your force." If you are implying or intending something more than that, you can ask straight out and we'll answer it.
There's debate about whether they should be listed on army sheets, but you can ask the judge's event if they care for them to be listed.

c) As Zandig already pointed out, the answer is no, but I've heard it joked that some players like figures on their sideline that aren't part of their team in order to act as "cheerleaders" (the X-Men girls watching from the sidelines like a football game, for example). Examples like that are not legal as part of your "sideline," but they are allowed as just random figures on the side of the map that are just there for no reason, same as having 2 extra pair of dice if you wanted to.
My only point in saying that is that the "sideline" is a specific game term (that they have yet to fully define) that is different than something being on the side of the map.

d) Any power, trait, or anything that refers to the sideline or anything that says that you bring it into the game without specifically saying "from outside the game" would have that thing on your sideline until it is brought onto the map. No need to split it, but you can organize it any way you'd like to.

e) Yes and same thing. Anything you'll potentially be bringing onto the map at some point during the game (that isn't listed as "from outside of the game") should be placed in your sideline.

f) Actually, this is a "we don't know right now" answer. They did rule it a while back with Black Talon (although I can't find it now... either they deleted it or I'm just not searching for the right keywords) that KO'd figures were put on the sideline (so you could bring them back into the game with his power, then remove them again to go back to the sideline) and "spawned figures" (eg. Iron Legion, Multiple Man, etc) have always been placed on the side of the map, but none that come to mind have ever said that they are stored on the sideline.
That will be one that may not have an answer until they put out the new rulebook or they may just skirt the answer as they have for the past couple years... until then, it doesn't matter if they are in an "official" sideline or just off to the side of the map.

I assume this is still valid?

http://heroclix.com/heroclix/the-many/

This implies KOed figures go to the sideline (which i did not know and don't have any idea how that works if you KO figures and have a maxed sideline, etc. Ask about that burleigh!!)

http://www.wizkidseventsystem.com/bb...f=3&t=3714&e=0

It's not invalid, but it's never been expanded on. Every time that the sideline has been asked about (Dragon being the big one to ask multiple times), the question has been rejected or only half answered. It's our HOPE that they are going to give a solid description about the sideline and what all happens there in the new rulebook. Maybe we're naive and maybe we have Blue Lantern Rings that are on their way to us because of our great Hope, but we are still holding out.

Until then, we don't expect WES to answer anything about the sideline beyond the few mentions of it (on a few figure's character cards and that statement you cited).

Either that's one that they missed when deleting the other or the other had something that changed, but that is one of the statements that they made about that.
Maybe they'll say that the limit of 3 per 100 points is only for building your team and doesn't apply after that (like themed team guidelines when your keywords change during the game)? Who knows at this point.

So, let me see if i got this:

a) They are not on the force. So things like "If X is on your force" and the new end-game rules don't apply.

b+c) Sideline is part of your force for PRime/Unique/Legality reasons.

d) In 300 points i have 9 Sideline slots. If I'm using the legacy set and have 6 Pyms on the side, i can only use 3 Ants/Giant ant.

e) This one still confused me. If I'm playing Lobo in a 300 point game and have 5 sideline guy, i can put only 4 markers on my sideline to use as Lobo Clones and he can't get more clones than that? What about Chase Thanos? Do i have to use sideline slots for how ever many Golems i plan on using?

f) This still seems to be up in the air

For all answers, I'll give the caveat "as of the current understanding" as they haven't really given much information.
But yes, they don't count towards the force on the map (so figures that get bonuses when FigA is on the map/force won't get those bonuses, including the number of Horsemen of Apocalypse are on the map for their ATA). They will count towards the figures you bring (so you can't have a Prime on your sideline if one is on your team on the map, covered in b/c).

Right!

Yep (at this time). Note that some venues that are more casual may not care... ask your judge if you want to (or expect to) have more than 9 figures on your sideline in a 300 point game.

For figures that create a "Bystander as listed on the back of this card" (or similar), they haven't really said how that works with the sideline as of yet. Since they aren't separate figures (meaning those with a clickable dial), it could be argued that they aren't separate figures until they are on the map or that they can be represented by tokens... that would be a good question to ask on WES after the new rulebook comes out as the sideline was more intended for replacement figures and preventing a shoebox full of potential replacements (which would more serve to slow down a game than facilitate how a figure works).
The Thanos question is a moot point as his power says, "...if no friendly Stone Golem tokens are on the map..." so you can't have more than 1 on the map per force.

Yep! They haven't said what the limit of 3/100 points is for, but based on the little information they have given, I would imagine it's for the build of your team, not for the entirety of the game.

Good questions overall and a few that I hope are answered more officially soon!