Check If Else
This blue Control Flow block allows you to run one set of blocks if a test is passed and another set if it doesn't pass.
Define your test in the blank beside 'Check once if' text. A test might be 'Dino's X position is greater than 10'. If it's greater than 10 do one thing, otherwise do something else.
Very important: the test will only be checked once! To continually check your test, put your 'Check Once If' block within a 'Repeat Forever' block.