Against gragas, Look for extended trades whenever possible. Gragas relies heavily on his abilities to deal damage, but if they’re on cooldown he cannot really do anything except for auto-attack. Go for extended trades when one of his abilities are down.
 
Gragas can tease an engage when his Body Slam E is up. Try and stand behind or near minions at all times. However, do not stand too close to them since the ability does have an AOE and if you’re close to them, you’ll be hit by his E.
 
If Gragas uses his W, it’s because he wants to do something such as setting up his Jungler or going for a trade. Play safer for a short period of time whenever he uses his W. Against gragas, Look for extended trades whenever possible. Gragas relies heavily on his ability to inflict damage, but if they are on the cooldown, he can really do nothing except self-attack. Go for prolonged trades when one of his abilities is down. Gragas can tease a engagement when his Body Slam E is standing. Try and stand behind or near the minions at any time. However, do not stand too close to them since the ability has an AOE and if you are close to them, you will be hit by his E. If Gragas uses his W, it is because he wants to do something like set up his Jungler or go for a job. Play safer for a short period of time when he uses his W.