Hi.

1) It depends. If this was just a wandering monster, new one should not spawn just because you killed this one. If this spider came from Albino Rock Spider's Lair it's possible new one will respawn later, it's hard to tell without knowing what kind of lair it is. Though I guess if this was a solo spider no new ones will spawn,since usually they spawn by 3 from that kind of lair.

2) Empire v Human -> various races of Men are Kingdoms, various races of Fallen are Empires.

Thank you very much guys I also got another question: A warg provides 10 dodge and 15 ranged dodge. Does that 10 dodge get added to the ranged dodge and makes it a total of 25 versus ranged attacks, or is dodge only for melee attacks, and ranged dodge only for ranged?

Also, if I upgrade an outpost that is linked to a city that is linked to other cities by area of control, will the entire area, including those around the other cities get the benefits, or only the area around the city the outpost is linked to? And if the latter one is true, how can I see one city's borders when two cities are linked?

Also, got another quick question.. Does the +3 move and attack on first turn stack with the +3 move and attack you get from fortress?

Not quite...  I have seen green lairs spawn a new monster and revert to purple a few times, but it takes quite a while for them to do so.

What it looks like to me is that the purple symbol means that there is a live monster somewhere in the area which lives in that lair.  Kill all the monsters spawned from that lair (or maybe there's only one tied to it?) and the icon flips to the green one, but this may or may not completely stop new spawns from the lair.  No idea how it's scheduled, though - in some cases, I've seen a green lair spawn a new monster and revert to purple within 5 turns; more often it'll still be green and empty 100 turns later.

Good point - the territory point is also very relevant here.  I've never seen a green lair flip back to purple after my territory expanded to cover it.

The specific case that I'm primarily referencing was an (IIRC) ignys lair in the fire wildland.  After conquering the wildland, I planted a couple cities, but my sov was needed elsewhere, so he immediately ran off after I finished cleaning out the remaining monster stacks, leaving this one lair behind, since it was green and therefore no threat.  It was positioned just right so that neither city's territory covered the lair and, after many turns (I would guess maybe 20 or so, but wasn't keeping track), the lair released a new monster stack and reverted to purple.  Aside from the color change, I also know that the monsters had to have come from that lair because it was bordered by my territory on two sides and by mountains on the other two.

I know I've seen it happen other times, but that's the one that mainly sticks in my head, probably because it was the first time that I noticed a lair having definitely come back to life.