Disclaimer: The following guide is a copy of instructions given in a training secession via AC, also the sole purpose of posting this guide is for these players to re-read this. As a result it isnt particualy well written and some minor details are probably slightly off.

For all reading this i would advise reading the following guides before attempting a compact defense:

Myself: bbs.evony.com/showthread.php?t=146859
Darkbrady: bbs.evony.com/showthread.php?t=63051
Hellfire: bbs.evony.com/showthread.php?t=128060

I would suggest that only players with a decent understanding of battle mechanics should attempt this.

A compact defence (CD) is a 0 trap/abatis/defensive treb defence. V.effective offline, strong all round. You will always take some losses against any attack BUT crucially you wont take the usual 200k swords lost vs archer rainbows.
As most people use archers as the main part of their army this defence is particularly useful.

Suggested Minimum Setup:
100k swords, 100k pikes, 200k warriors, 25k cav, 25k Phracts, 250k archers, 20k ballistae, 5k rams, 5k catapults
Always include 1 layer as a scout bomb block, but unlike the standard ?5k? defence you can use swords as these will be protected ? 2 layers of bomb blocks are v. useful for adv.players.

So before you use this you need to understand how archers work:
They will attack any units in range in this order: range - closest - highest attack total
So in other words, if they have defending range in their sights they will attack these first (starting with highest range too lowest - ATs, Pults, balls, archers) in that order.
If there is NO range units in the attacking archer range then they will attack the closest other unit to them - this is normaly the fastest unit. so - cavs, phracts, pikes, swords, warriors, workers, rams
With a compact defence - the battle field range is set by the highest ranged unit - this is ATs & logs.
As ATs are classed as 'ranged' units they will always attack other 'ranged' units first
*key point* So even before the attacking archers have hit anything the defending ATs will have done severe damage to them
The attackin archers will move forward - it will take the archers exactly 1 round to be in range of the walls
BUT after round 1 the attacking archers, pults & balls (benifiting from wall range boost) will also be in range of the archers - they will then all attack the attacking archers
so.... if you have enough archers, balls, pults & ATs in your city to '1 shot' 100k archers then you will take near 0 losses
in a CD your layers are safe from attackin archers
which is why it is sooo strong
the layers (pikes, swords, cav, phract & warriors) are used to stop cav/phract bombs from reaching your archers
as even the strongest players only ever have (at very most) 300k cav & some phracts - the layers suggested above will withstand this

so... in summery:
As the battle field is so short the defending layers will stay close enough to the walls & defending archers so that they are not touched by attackin archers. For example: look in your barx - hover your mouse over the picture of archers speed of archer is 250, now look at pikes - its 300. Now factor in speed boosts to get: archers 500, pikes 600 As attackin archers will reach the walls in 1 rounds your pikes are only 100 paces ahead of your archers. Archers move 500 paces in 1 round - so in defending archers & pikes will get into the attackin archer range at the same time