Update: I hit another 2 infests and they both returned big payout.

So, in short, infest banks didn't load up and return troops as they should. Instead, they loaded up 3 times as much and returned 1/3 each, for the next 3 levels.

Devs might want to look into it, as it's an obvious bug, since that's not how it's intended to work.

P.S. Just to make clear, I do infests starting from lower levels and going to higher ones, so it's not that I hit high level ones and got big payout of low level one. I started hitting 203-204-205-207-210... total of 11 locations and got big payout worth nearly third of what I put in at 215, so overall, my army decreased by 1/3. Then, I came here to post and whine and then I said "screw it", went back to game, hit 217 and 220, which added with 215 seems to be the 95% of what I put in previous infests alltogether.

P.P.S. It's still a bug, so I suggest to look into it.

No one said that's how they're supposed to work...  It's not a bug, on average they return about 95% but there's a lot of variance built into it.  The troop type of the payout also seems to matter, some give more res value than others (with bc and int payouts being the biggest, and qc/pc ones being the smallest in my experience).  Partial payouts are also common, sometimes after a partial payout you get the rest out on the next infest, other times you have to hit a bunch more before you get another.  

True, but I think it could be a bug, because it's supposed to pay out when infest bank is full. Should be consistant in its rule. If there's a chance it skips the payout and continues gobbling up the army, then it could cause an infinite loop. In my case, it was 3x the banking value that it took.

As in, devs stated, that when you hit a threshold for big payout, you get it. (I believe, it was 2015's post on facebook). I just took it as an implication, that that would be the case, although they didn't directly say there was not a chance it could skip the big payouts and return them later, so that could be the case too.

Also, I was doing first time clears on 321 and 322, but they sucked up my army and gave way less (25k interceptors spent, 7k returned). Have you had that kind of experience?

As in, not revisiting, just first time clears.

I think the game starts freaking out when people start spamming infests with big numbers of troops when CvC or exp tournaments are on. I just hope I get them back while doing regular infests xD

I have noticed sometimes I won't get a payout when I'm expecting one, then get multiple payouts later (or one bigger one).  There's definitely randomness built into the system, it's not a hard rule of whenever you bank a certain amount you'll always get a payout.  I think it's more you won't get a payout unless you've banked at least the required amount.  

Yeah. I think, if it's part of the game design, then that's a major problem, since all of a sudden, tax isn't 5% static anymore, instead it can be 10%/15%/20%... etc... Also, unless you have over 200k+ air or artillery, it discourages you to do infests, since they eat a lot. Like in my case today, infests ate 102k interceptors and started returning the troops only afterwards.

Although, if it's not a part of design and is a genuine mistake, then it could be fixed I guess.

You know? When I came across your comment years ago, when you said "infests should be done only to convert your troops" or something along those lines. I didn't believe it back then. I thought, if there's tournaments and they have quite a big point cap, there should've been a way to profit from doing them regularly, but now I understand xD

infest tend to work better after the reset early in the morning, the more infest you do in the same day the more troops they eat if you kill so many troops in the same day you will always end up losing no matter what u do. killing 102k ceppies there is a very reckless move for your part. at this point everyone should know that infest are designed to make the player lose troops in the long run so if you trully want to benefic from them you have to implemnt an strategy where tournaments, queues and plarium's presents they give from time to time with troops are adecually used to convert every time you make infest into wins of the troops you mostly want and keep accumulating. as easy as that.

Overall the average is 5% loss, but on any particular payout you could end up with 10% more than you started or down 20%.  It's like flipping a coin, over time you'll end up with about half heads and half tails but you could get heads 7x in a row and that doesn't mean there's anything wrong with the coin, it's just luck.  

It's generally not possible to make a profit on infest tournaments, even if you have good bonuses (so it takes fewer troops to kill each infest, and you get more points for a given amount of troop losses).  For example, one of the best events in terms of reward value to points needed takes 150k points to complete and gives you 500 excals worth 9.3 mil res (it also gives some infantry but their res value is negligible).  Scoring 150k points means killing about 4 high level infests.  If each one takes 10k interceptors and you pay a 5% tax, to score the points you lose 10,000*4*0.05=2000 interceptors, worth 15 mil res.  So if you have troops you want to convert anyways you might as well do it during a tournament to get the rewards "for free", but if you're sacrificing good troops just to score points at best you'll about break even.  

You infested 102k ceppies??? Good lord have mercy, my soul cannot take this