If you mean after a certain amount of turns the reinforcement drops start popping 8 squad pods every turn. Yeah, there's info about it in the configs. You can up the turns if it bugs you.

There's also a sneaky mission where every civilian on the map is a faceless. That's fun...

A couple other surprises, but I don't want to ruin them for you.

take 4 reaper shinobi and run around stealthed until it pops then reap reap reap until you wipe
best killstreak wins a cookie

@eldiabs- yeah.... long story short I tried to take a "destroy the monument" mission with 2 stealth shinobis, and I ♥♥♥♥♥♥♥ did it to; 2 stealth shinobis took out 10 enemies including two Mutons and an Archon in the same pod. ...the first 8-man pod dropped the turn I was going to kill the last Muton >.< But more importantly- do you know if it serves an important balance purpose? This wasn't cheesing the mission or exploiting- I just had to be that careful to get it done.

@superweiner10- A) I was running two stealth-specced Shinobis, B) I don't have above a Tech Sergeant Shinobi right now, and C) Please explain to me how to kill a Iron Skin 13-hp 3-armor Heavy Mec? Also, what do I do if a Berserker drops and counters the Reaper attack?

I think those 8 enemy pod spawns are meant to get you moving. Sort of like soft timers.

Oddly enough I've never had reinforcements on monument destroy missions...unless I failed a lamp hack with a reinforcement penalty.

So...could be a trap mission you ran into? Dunno...

Ithuriel, I was joking, you obviously don't want to sacrifice 4 max rank shinobis except for the lolz

@eldiabs- tbh that's likely because you've never taken as long as I did. I had to do things seriously slowly with an awful lot of shenanigans and LOS breaking in order to survive.

Hehe, nice screenshot ... makes me tremble.
Did not experience something like that till now, but I always try to get in and out as fast as I can, and therefor I reload much more often then I do normally, even so I dont really like this kind of playstyle ... and I play with easy war mod, so maybe this until 1.2 never will happen to me ... hopefully.