At the moment, it's Sung doing all the betting and providing the aggression attempting to chip away at his older opponent. Vilandos is much more happy to play defensive and check-call, occasionally making big shoves, perhaps thinking he can make Sung fold many hands unless he has a monster.
The question is will Sung find a hand one of the times that Vilandos makes a big push, or will Sung bluff into the Greek player's hands?