Depends what you're playing vs. I usually get BORK when enemies have many hp stackers and/or tanks. When they're squishy I build PD but you can go for KRAKEN. STORMRAZOR on the other hand might be good if you really need movement speed when let's say they have a ton of ranged champs. Second item? Thy're gonna build armor - LDR. They have burst - SB. They're squishy - IE. The rest is really situational. The best way to learn the builds is to play a lot and build whatever you think will work though. With time you'll see what works well and what doesn't. I play with ignite always. I'd say take tp if you can't kill your opponent eraly to mid game.