Ensures tutorial is a shambles — that's a risky game! (7,8)
I believe the answer is:
russian roulette
'a risky game' is the definition.
'ensures tutorial is a shambles' is the wordplay.
'is a shambles' indicates an anagram (letters rearranged chaotically).
'ensures'+'tutorial'='ensurestutorial'
'ensurestutorial' with letters rearranged gives 'RUSSIAN ROULETTE'.
'that's' is the link.
(Other definitions for russian roulette that I've seen before include "highrisk game" , "suicidal undertaking" , "risky business" , "Deadly gamble" , "Dangerous game of chance" .)