As usual, the wiki's theme is changed whenever a holiday celebrated as a Chicken Invaders edition comes around.
This time it was halloween. The event lasted from October 25th 14:00 UTC to November 1st 15:00 UTC. It was purely cosmetic.
Here's how the wiki looked like back then.
On a side note, we're getting closer and closer to Chicken Invaders 6's release! It should come out in less than a year.
Previous editions: