I think the christmas mob should be an Evil Santa!
3 blocks high, 2 blocks fat santa throwing snowballs at you which will knock you back but deal no damage.
Rewards should be GIFTS which you can open and get a RANDOM item all the way from gravel to a diamond block!
I hope you are joking...
I support nekos!
Link: viewtopic.php?f=6&t=28798
Gold would be too much IMO.