Forgo the velvet lawns and manicured hedges! Extreme croquet, a whimsical cousin to the garden pastime, casts aside such constraints. Played by adventurous souls on terrains most peculiar, this croquet defies boundaries, both literal and metaphorical. Prepare for wickets woven amongst untamed landscapes, where the sporting spirit meets the unexpected.
More here - Extreme Croquet at Wikipedia
Here's a little short on Boston University's International Extreme Croquet Society