Sometimes when I attacked other player, I try to count how many defenders in their castle. Sometimes I found an extreme numbers.

Then I experienced my self the glitch of my own clan castle.
My clan castle is level 4 that have troop capacity 25. I asked for reinforcements troops to my clans, someone gave me a dragon and a giant (capacity = 25). Then I log out. attacked by someone and got 12 hours shield.
when I logged in back, I saw my replay, and something strange happened, the troops that got out from the castle are a balloon, giants and barbs and goblins. Strange, where is my dragon?
Then I attack someone else, I use castle reinforcements troops. Came out from the castle, barbarians, goblins, giants, then finally ... a dragon!!!
If I counted my reinforcement troops, their numbers were more than 25.

Strange, huh!?