On 0 servers with real players, out of 13 Steam servers that run it now, fakes and empty ones included. Checked 02:06 UTC.
kz_grotto is a KZ (climb) map: you jump your way to the end as fast as you can. It is not one of the maps that come with the game, so servers send it to players from the Workshop when they join.
Over the last 30 days kz_grotto was the #531 map on CS2 community servers, with 3 real players on it at any moment on average - 0% of everyone playing. It ran on about 2 servers with real players at a time. Right now 0 people play it on 0 servers. It is busiest on Tuesday around 16:00 UTC and quietest on Wednesday around 00:00 UTC.
Right now 0, on 0 servers from the Steam server list. Over the last 30 days it had 3 real players on average at any moment. Fake servers and bots are not counted, and Valve matchmaking is not in the list.
On Tuesday around 16:00 UTC. The grid above shows every hour of the week in your own time zone.
The busiest right now: FemboyKZ - CS2KZ | AS Public (0 players), FemboyKZ - CS2KZ | NA Public 2 (0 players), House of ReDMooN - CS2KZ (0 players). The full list is under "Servers running it now", and every server has its own page with its history.
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