One of the two arena maps, in comparison with bitty grass, it has fewer obstacles and has columns instead of walls. You only have a sword and you need to fight off your foes with it.
Snowy ruin was a battlefield in what the noobs and zombies, after battling a lot they couldn't afford for more weapons except the sword, and they used it.
Try to get to high places if you have O lives left as perks are disabled and you can't equip high jump perk.
You better stay on columns as if anyone tries to charge at you then they have a high chance to die.
Staying in groups is effective.
Getting to hard to reach places is effective as you can't get shot at.