How To Win Any Siege Defense Using Overpowered Gate Oil

I remember my first run in with overpowered gate oil. Was playing my German campaign and attacked the southern city in Britain. I landed all but one of my troops and proceeded to run all the units to the front gate. I lined up three units near almost next to the gate and they started throwing their torches. To my surprise I was taking heavy casualities. Well that's when I noticed overpowered gate oil for the first time. I thought it was neat, backed up a little and burned that gate down. The ordered all three of those units to go through the gate. To my surprise an almost unending stream of overpowered gate oil proceeded to pour of the gate and on top of my units. Only about 20% of those three armies made it through that overpowered gate oil and proceeded to be routed by the units on the other side, which made them run for their lives straight through overpowered gate oil once again "A unit has perished".

I decided to use strategy this time, so I took 1 unit and had it go right next to the gate, which caused overpowered gate oil to pour out and kill maybe 10 of those guys, and then it stopped. I knew that now was my chance. I ordered the unit to go through the gate now that the overpowered gate oil had stopped. Maybe 15 guys made it through before overpowered gate oil started pouring again, killing the other 120. I knew then that Creative Assembly maybe spent 5 minutes balancing overpowered gate oil. I was utterly defeated. I got the rest of my troops the ♥♥♥♥ out of there and switched my research over to the siege field. Now I can't lose a city defense battle.

Well after that story you're probably wondering "Gezz, how do I get overpowered gate oil?" Well, that's simple my friend, research. First you gotta research the main military technology (2 turns) then start researching the siege field. Below is the German Siege tree.

After researching Supply Foraging (2 turns) you can now start the siege tree. Emergency Measures takes another 2 turns and Great Food Vault takes 3 turns. Finally, you can research Boiling Oil which is 5 turns, meaning that you can have overpowered gate oil by turn 13. Now let's take a look at the Roman tree.
As you can see, Rome gets overpowered gate oil a lot earlier than Germans. After researching Supply Reforms (2 turns) you can start Rome's siege tree. Armoured Siege Units takes 2 turns to research and then you have Boiling Oil with 4 more turns. So, as Rome you'll have overpowered gate oil by turn 9.

Now that you've unlocked overpowered gate oil, it's time for the hard work to start.

So, now that you have overpowered gate oil it's time for the hard part. Below is a 5 step guide on how to properly use it

1. Get into a city defense battle.
2. Place your units properly. Form a U-shaped army around the entrance to the main gate(s) they're going to attack and put your range units on the wall. Set the range units to flaming ammo.
3. Start the battle.

Now start's the hard part.

4. Go and grab yourself a sandwich, watch a movie, read a book, or better yet grab your ♥♥♥♥ and wait for the other army to burn down your gate and get themself slaughtered by overpowered gate oil. The few troops that make it through the bottomless cauldrons of overpowered gate oil will end up attacking your U-shaped army and will be immediately routed since they lost 80% of their forces running through the overpowered gate oil.
5. End battle.

See this screen shot? Got attacked by 2400 units. 200 died from flaming arrows and javelins and 1800 are laying in that pile from overpowered gate oil. Maybe 5 made it through which you see dead on the hill next to my spearmen. I've talked to people who've won 2400 vs 400 battles easily due to overpowered gate oil. Nice work Creative Assembly. Rome 2 was ready.

Here's a video how to use overpowered gate oil correctly. I used papa john's pizza as an aid in this battle with an ice cold sprite. Had a lot of audio problems with the editor. It was like the editor knew that overpowered gate oil was well overpowered and distorted the audio!
Now you know the secret of winning any siege defense, go forth and conqueror. Also balance and bug test your game next time.