A two-player race

By the end you will have two racing cars on one keyboard, and a flag that says who got there first.

What you need

The racing car movement is Advanced, so switch the mode to Advanced first.

Two cars	+ Add object → Library → Racing Car. Add it twice. Name them Car 1 and Car 2.
Flag	+ Add object → Library → Flag. Put it at the end of the track.
Walls	Blocks with Is it solid? set to Solid (blocks everything), or Stone Wall tiles.
Winner text	A Text object called Winner. Untick Visible when the level starts.

Click empty space in the level so the Level settings show. Set Gravity pulls to Off (everything floats). Cars seen from above do not fall.
In the Properties panel, open Whole game → Player keys. Tick Two players on one keyboard. Pick Player 2's keys, like W A S D.
Click Car 1. Under Movement, How it moves is already Racing car (seen from above). Set Moved by to Player 1.
Click Car 2. Set Moved by to Player 2. Try a different Top speed for fun.
Build a track with walls. Leave a gap wide enough for both cars.
Open the Events tab. Click + New event, click Car 1, then Collides with another object → Flag.
In the Winner cell choose Set the text and type Player 1 wins!, then Show. In Car 1 and Car 2 choose Stop.
Right-click the row number and choose Duplicate. Change the copy to Car 2 and Player 2 wins!
Press ▶ Play level and race a friend.

WhenCar 1 collides with Flag

DoSet text of Winner to “Player 1 wins!”Show WinnerStop Car 1Stop Car 2

WhenCar 2 collides with Flag

DoSet text of Winner to “Player 2 wins!”Show WinnerStop Car 1Stop Car 2

The ☻ Player 2 column appears in the Events tab once two players are on. Use it for Player 2's score and lives.

Give points: Add to score for Player 1, Add to player 2's score for Player 2. Add a Score object with Shows set to each player.
Add Lava from the library. Collides with Lava → Set position back to the start.
Make it a time trial: a Timer display that counts up, and a High scores table on the next level.