One of my fave games is sk or Smash karts!
You basically smash people in the classic game mode. There are multiple game modes and I have listed them below:

• Capture the Flag
  Classic Free For All
  Hat Holder:
  You hold the hat for 30 seconds usually without anyone shooting you down
  Gem collector:
  Collect ten gems first. They spawn around the arena randomly.
  Teams Free for All:
  Basically free 4 all with two teams- red ‘n’ blue. It's either score target or best in 3 minutes.
  

Arenas:

• Slick ‘n’ Slide
  Gravel Pit
  Smash Island
  Smash Fort
  The Old Graveyard
  Graveyard
  Lavapit
  Space Station
  Snow Shrine
  Snow Park
  Sky Arenas:
  Sky arena Pinball
  Sky arena Temples
  Sky arena Showdown
  Sky Arena Temples
  One I can't remember
  CTF arenas:
  Smash Island (same one as above)
  Smash Fort CTF
  Lavapit CTF
  Graveyard CTF
  Snow Park CTF
  Sky Arena Temples (Same as above)
  Sky Arena Tunnels (Same as Above)
  Space Stations CTF
  

Play official here (Ads may not work)
Play on Crazygames (Ads will work)
Btws:
It is an online multiplayer game.
Pro players:
Bossangeles (Legend)
Tom Cruise (legend)
Diamond Blade (Current world record holder and Moderator)
Alphonso (Pro)
Joe the pro or JTP (Moderator)
AlphaZero (Legend)
Atomic Fire (Pro)
Storm (Pro)
Xcellence (Pro)
RayDay (Best Trickshotter ever and Moderator)

smash karts