Well, there are a few ways to keep cats from climbing or playing with the Christmas tree. You can try placing aluminum foil or double-sided tape around the base of the tree to create an unpleasant texture that cats won't want to step on. You can also try using a motion-activated air canister or spray bottle to deter cats from coming near the tree. Another option is to provide your cat with a more suitable alternative for climbing or playing, such as a cat tree or scratching post.