Waterpolo,
@Wibble? Basically everything that's happening underwater...
At the highest level there is relatively little underwater cheating as you don't have the time to both do your job and foul underwater plus retribution can be brutal if the refs don't protect players.
The rules are also very specific with defenders getting kicked out if they make contact with the attacker when they don't have both hands in the air (and the attacker has released the ball). So a typical kickout would be the ball is passed into centre forward. The centre forward releases and leans back into the defender earning a foul/kickout. If the attacker is still touching the ball he is fair game barring brutality/punches or a head hit. Basically penalising the defender for poor positioning and not having their hands up.
My son now plays pro in the Greek 1st Div and this is an example of a CF earning a kickout. He then scores on the next extra man powerplay.
The other thing is that the contact allowed is far greater at the highest level, so further illegal underwater contact isn't as neccesary. In this clip he scores after being smashed and it probably wouldn't have even been a foul, much less a kickout, if he hadn't scored.
Reffing at lower levels can be terrible and players then tend to try to simulate more and then fights tend to follow when refs lose control of games.
That all said things do get missed and incorrect decisions made due to referees having to make decisions at distance for things that happen underwater.
Simulation (exaggeration) does occur but at the top level doesn't occur very much, even if it does at lesser levels. To address this FINA have introduced specific penalties for simulation this year.
I should mention that strategic fouling is an intended part of the game. Which is fairly unusual in sport. However, water polo wouldn't work as a sport without it. Rules have been introduced to better allow the playing of advantage if fouled when attacking, with referees allowed to award fouls/penalties if they let the play go and a goal doesn't result.