This question has been bugging me all day. I have never seen Survivor, but I know a little bit about it just from the commercials, but here is a great site(TV_series) that describes it in detail and I think it will give you some great ideas about the types of games to play involving strength, endurance and agility and then blend it with regular stuff that has to do with getting married.
I’m thinking of some kind of obstacle course that involves picking up socks and putting them in the hamper, grabbing a beer out of the fridge, sweeping up a pile of something, and carrying a pan full of water or eggs from here to there—quickly!
Making everybody wear a tribe “buff” as described on the site, but put the bride or groom’s name on them.
Hiding an “immunity idol’ somewhere in the house or yard where the party games are going on and who-ever finds it wins a little prize. The idol could be some type of semi-naughty marital aid or lotion or whatever you like ; )
Maybe the guests are made to dig in a big wheel barrow full of mud to find some object (there’s lots of mud on survivor). The mud would be filled with lots of odd little objects, but the winner is the first one to find the correct object (maybe a gum machine ring with a pretty fake jewel).