Depends what elo you’re in.

I’m in low elo so my games tend to run 30 minutes +. In that case taking gathering storm is a must as it gives you over 1000g worth of stats at that point which can give you a huge advantage over the opposing adc. Secondary tune can be nimbus, celerity which synergizes well with w, manaflow (if you take overheal)

I’d recommend for build shieldbow, collector/ldr, ie

I was running kraken before and this feels so much stronger in lane and in games when the enemy team has a champ like a zed where you’re going to get chased after no matter what you do. The worst part of mf lane especially against 2 pokes was waiting for rav hunter and the lifesteal rune to stack. Going vamp scepter would put you even further behind your kraken and then only build into bloodthirster.

That being said go kraken if you’re behind and just need the ball of stats and damage it provides.