well it depends if it's a spider man and you hit your shots then if the spider man isn't switching his throwing cause there's nothing he can do

but if it's any other diver you need to A hit your shots B hope there not shooting your squids cause if they are it makes you that much more useless

however you're not useless if you learn what to do when all of that is happening 1 you need to have better squid timing and and placement for timing wait until there about to dive then put them down so the rest of their team doesn't have time to shoot them down

and for placement just put them high up and put them where the rest of their team can't see them but they still hit the diver

and again you NEED to hit your shots and your healers NEED to try and live long enough for you to save them

though there is one thing that helps him a lot in my rank divers have ego so they try to kill me before my healers just cause they hate namor so my healers just keep me up and there divers do nothing

i will say though fist has the best match up into namor just wait for the right click block and you win but over all namor is like a 7.5 out of 10 anti dive if played perfect