Hi,
Well, it took quite a while, as far as I understand, the movement of animals and aliens is random, so it remains to wait for them to meet :), but in any case I won!
Maybe if you replace the randomness of the animals' and aliens' movements with an artificial intelligence for the aliens, which would itself manage the strategy of abducting the cows, and you, in turn, could control the dogs - it would be even more interesting!
It was funny and fun, although I got a little tired of clicking on cows :D. Congratulations!