Hey there guys, I just wanted to tell you that this is the first guide I've ever made! I will try to do my best to keep it fresh, and detailed!

Before you just auto-lock in Ziggs and think you are going to rapeface, wait.
Make sure you have a pretty AD heavy team.
Tank > AD Carry > Jungle > Great Solotop (Blitz, Rumble, Nasus, etc.) > Ranged Carry
Ziggs = Ranged Carry
The reason I say you need AD heavy is because you want to scare them into wasting money on some type of defensive item. If you have an AP team all they have to do is grab a negatron early game and you're screwed. You need to have a good ratio, to where if they DID buy a negatron then the rest of your team would just destroy them, or if they bought armor you would tear them apart.
You need to confuse them into not knowing what the hell to buy since they will die either way.
VERY IMPORTANT Your ult is one of the best team fighting abilities out there. If your team is in the process of towerdiving, and the enemy team starts to retreat, toss your nuke behind them to ensure that if they run they will be blown into pieces, and if they don't you will all kill them anyway. Make sure that their survival is not an option.

Well RoA does give great sustain, and decent AP. But I'm not the kind of guy who likes to sit in lane and spam skills slowly wearing them down bit by bit. I like to take out chunks of health with each bomb. Ziggs has the best AP scaling with his skills next to Lux. Therefore rushing a Deathcap rather than RoA is the best thing to do. Because RoA takes so long to get to full capacity, and only gives you regen when you level, it would be worthless unless you picked it up first thing. So I just leave it out of the build to maximize the sick damage from Rabadons.

Ziggs shines brightest in middle. Probably the cheapest thing about his Q is that it can bounce over enemies if thrown correctly. Ziggs has extremely nasty range, make sure you use this to your advantage. If there is a wave of minions, and the champ is behind them, move back to give them a slight sense of security, then throw a bomb right before the first wave and it will bounce over them, giving that champ a blow she will never forget. Did I mention ALL of his skills do AoE? BECAUSE THEY DO!!!! Probably the cheapest thing to do is throw down a W at your feet, knock yourself towards the enemy (DO NOT DO THIS IF LOW HEALTH), Throw down a minefield behind them, then bomb them like crazy. Leaving them wondering what the hell just happened.
Another good way to do it, is get them down to about half health, and the second you turn 6 throw a minefield behind them, Q them, and ult in front of them. Because they will see the bomb bouncing towards them they will freak, run into the minefield, get slowed, and not be able to dodge the A-bomb you just tossed in their direction.
(ENSURE THE KILL)
If anyone ever is dumb enough to run into your minefield, ult them, the second they touch a mine you need to drop bombs like Hiroshima. Especially after you grab a Rylai's the slow will be so effective they will be at the epicenter of your Nuke before they move an inch.

I grab a Dorans in the beginning because it's just the best. The mana regen, and the AP is good enough for a nice long time of harassment. (IMPORTANT) The instant you get 765g you need to return, especially if you have already used clairvoyance. This is so you can maximize the gold you get from your Kage's Lucky Pick. You don't need to be raining bombs like no ones business in the beginning. You don't have the mana to support it. Only throw one if you know you will hit someone, or if you know you will not need to use any skills for a bit, and just need to farm some G. If the enemy team got smart and bought a negatron or any MR period. Pick up a Void Staff instead of a Rylia's.