i all ready sold the solution. i was forget to put it on a message i watch youtube and then it was easy ^^,
but when you play with 4 players it's almost inpossible to get the venom 4 times in a row. I know where everything is but i always miss one part to get the final venom with 4 players.
it's easy on solo with the gas chambers.
put 1 sentry gun on the one side and the sentry gun on the other side, and you stay in the middle between the two sentry guns. you can also walking between the sentry guns. with the kraken the hardest thing are the seeder turrets, they kill you so fast lol
with a minium life i won the game, I died 3 times in a row at the kraken. My turret was empty and the final shot i kill the kraken with my weapen specialist upgrade and then i died with the final hit, So lucky that i only died 2 times so the third time i get back on my feet and can watch de aftermovie of it.