@Noobby_Groovy777 I main Caustic, even though I like to play other legends for variety. His weakness is his hit box and being caught out in the open without much cover or good spots to place traps so avoid that. Use his barrels often and wisely, hide them whenever possible, use them when reviving to block line of sight and shoot them yourself when you need to buy time because this is a deterrent to regular players, but remember most sweats will push regardless because if they kill you the gas will disappear quickly. The ultimate requires the most effort due to needing good placement or it becomes very easy to avoid, it’s great in the final ring when there is nowhere to run and in tight spaces etc, remember to push a team that’s being damaged by your ult because they are also suffering other negative effects. His barrels also act as an alarm so keep an eye out for them triggering behind you, it gives enemy positions away which is handy. Hope this helps a little along with others advice.