This article is based on a discussion between the above mentioned persons on the Direwolf mailing list on what a Skaven Castle should look like and how the Skaven would Defend it.

The Skaven player need to make a map of the castle and the broken ground to mark equipment such as pits and Warpfire mines. The map and the marks don't need to be exact as long as they show the rough location of the traps, the location may differ by an inch or so to where the trap is finally revealed.

Tunnelsystem
The Skaven player can keep troops in reserve off the table and these can be deployed using tunnels or small holes leading through the castle walls. These holes can also be used to spring ambushes or sally forth through. Some lengths of the barricade may not be suitable for digging in and contains fake tunnel entrances with traps. The tunnelsystem and its size determins how many troops can be kept in reserve. Each Tunnel section that you buy allows you to place 3 wounds of troops in reserve ready to spring ambushes or sally forth, count the full number of wounds for Monsters and total number of wounds for warmachine crewmen. Total up the number of tunnel sections and multiply the number by 3 to get the total number of wounds that may be placed in reserve. I have chosen to limit the reserve by wounds as it prooved to hard to come up with restrictions based on models when you can deploy multiwound monsters and warmachines with two crewmembers. 3 Chimeras in reserve is different from 3 Clanrats in reserve!

If you want to you can allow the attacker to move into the tunnelsystem to fight the Skaven. Though in this case you need to set up a table with a small tunnel complex laid out, you can use the floorplans from Warhammer Quest to create the tunnels. Lay them out and have the Skaven player mark traps and entrancies on a seperate map (lots of bookkeeping for the Skaven player). Each square equal 1" and you can fit a single 20mm or 25mm base per square, 40mm bases takes up 2*2 squares. The tunnels are difficult grounds for non-Skaven. Now these suggestions are only meant to allow fast tunnel fights and they do not simulate tunnelfights very well. There is an excellent system on http://mad.ne.mediaone.net/Cave_combat.asp to handle proper tunnel fights.

You must buy the troops in the tunnel system seperatly but they do not need to be bought in legal units, IE they can be bought in units of less than 5 models. You can't buy standards, musicans or Characters but you can buy lone assassins. You can buy large monsters but they may not be taller than 10', or like a Rat Ogre, so no Dragons, Chimeras and similar sized monsters are assumed to fit into the tunnelsystem. You may buy portable Warmachines like Warpfire Throwers and Jezzails but not Doomwheels or other tall or stationary warmachines. Giant Rats need to be accompanied by a handler but Rat Ogres may be bought on their own. It's assumed that large monsters or Rat Ogres are chained to a wall in the tunnel or trapped in a cage and that they are released when the time is right.

Points cost: 10 points per tunnel section, each section allows you to place 3 wounds in reserve.

Ambush holes
The Skaven castle contains a tunnelsystem that allow the Skaven to keep troops in reserve off the table. The Skaven castle has tunnels or small holes leading through the castle walls and these holes can also be used to spring ambushes or sally forth through. The ambush holes should be roughly 60mm wide and 40mm deep to allow three Skaven to fight abrest or a single large Creature to fight alone, you should be able to fit in three additional skaven in a rear rank. The total number of models that may be kept in reserve is restricted by the size of your tunnelsystem, each section allow you to place 3 wounds in reserve.

The Skaven player must create a map that displays ambush holes and connecting tunnelsections. The drawing should be large enough to actually allow models to be placed there. Before the battle deploy your reserve troops on the tunnel map, you must deploy all the troops and they must be placed in units if bought as units. There is no upper limit to the number of models or wounds that may be placed in a single connecting tunnelsection, the size of the tunnelssystem is only an abstraction to determin the overall size and number of models that it can hold. In the Skaven movement phase you can move any models and units from one tunnel section to another, but only models that started their turn in a tunnel section may use that tunnel section's ambush hole.

Here is an ASCII example of a map. The numbers corresponds to the Ambush hole markings on a larger Skaven Castle map and models are placed in the tunnelsections to show where they are lurking.

| |    | |    | |
| |    | |    | |
| |    | |    | |
 1      2      3 

|  |___________________|  |
|__|   1           2   |__|

There are dangers with tunnels this close to the surface and with the crumbling constructions and poor maintenance of the Skaven there is an ever present danger of cave ins. If the wall section with ambush holes in it takes damage there is a chanse that the tunnel sections will cave in. Roll once on the Cave In table for each attack on the wall section that cause a result other than "No Effect", note that if there are several ambush holes present in the wall roll seperatly for each tunnel section. The results "Severly Shaken" and "Collapse" adds +2 to this roll.

D6 Cave In Table
1-3 No Effect
4+ The tunnel section caves in.

If a tunnel section caves in its ambush hole is blocked and may not be used anymore. Further roll a dice for each model, add +2 to the roll for large creatures, and on a roll of 4+ the model is crushed and removed as casualties. Models that survive must use their next movement phase to move to another tunnel section.

Points cost: 20 points per ambush hole. You must note the location of each ambush hole on a map.

Trenchsystem
The ground infront of a wall or tower consist of collapsed pieces of the wall or tower and a multitude of scrap and debris, this is called the broken ground. Its not uncommon to find that the broken ground have been dug out to form a trenchsystem and part of the trenches has been turned into barricades by adding sandbags, logs, bricks and even doors pulled of their hinges. Skaven units may deploy in the trenchsystem if they wish to, these troops do not come from the reserve troops and they are bought as normal regiments and must be bought in legal units. The barricades count as difficult terrain and as defended obstacles if a Skaven unit has taken up position behind them. Depending on the actual tabletop terrain the barricades may also count as hard cover.

The trenches should be roughly 40mm wide to allow two ranks of Skaven or large creatures such as Rat Ogres to be placed there. The trenches are not ramparts and no rules apply for ramparts unless otherwise specified. Skaven may fight in two ranks and combat resolution is counted as normal. Troops in the trenchsystem do not benefit from the Leadership bonus but are affected if the castle is breached. Two Skaven units may move past each other in the trenches if they are both in a single line. This is done just as if they had moved past each other on the ramparts, see Siege page 7. Models in the trenches may perform a "man the walls" charge reaction and may move from a barricade to a gap in the barricades.

The barricades should be placed just outside the rim of the broken ground and the Skaven defenders should then be placed in the broken ground. However depending on the actual tabletop terrain it may not be possible to place models there and the Skaven player may then move the barricades a couple of inches out from the broken ground. Unlike a normal castle its not easy to know how each Skaven player decides to build his castle and the actual tabletop terrain may look very nice but may not be ideal for placing models.

The intention of the barricades is not to form an unbroken line of barricades that will block of the attackers from reaching the walls. The barricades should be 4-6"long and there must be a gap of atleast 4" between each length of barricades so that the attackers can reach the walls. The Skaven units can of course move to block the gaps but they will not receive the bonuses of a defended obstacle.

With the permission from the besieging player the trenches with barricades may be deployed in several lines and this may make it very tough for the attacker to reach the castle walls. This will mean that the trenches are deployed further away from the broken ground. In this case you should consider giving the besieging player more turns to reach the castle and possibly also removing the Skaven players +15% points increase for his defenders. If you are fighting with a low castle you may always deploy barricades in several lines of defense.

The Skaven need to be able to move in and out of the castle freely, especially with carts or large goods. Therefore the ground before the gates must be free of broken ground, trenches and barricades.

Points cost: Trenches cost 20 points for a single 4-6" length of barricades.

Warpfire mines
The Warpfire mines are fiendish devices that is something like a Warpfire thrower buried under rubble and is triggered when a lever is stepped on or when a beam or rock is removed to clear the way. The mine will explode and shower any present models with burning Warpfire. They are often placed at the base of walls to disperse attackers that tries to deploy ladders to climb to the ramparts.

The Warpfire mines may be placed anywhere within the broken ground, including the trenchsystem, or before or after a gate. This is an ASCII example of how the mines can be marked on a map.

|  |___________________   |
|__|         M         |  |
   Barricade        M  |__|

When a unit or model touches the mine, counted from its rough location on the map, roll on the Warpfire mine chart to see if it was triggered. If the mine detonates the first two ranks are hit. Roll a D6 for each model and on 4+ the model is hit and takes damage as if hit by a warpfire thrower.

D6 Warpfire mine chart
1 The mine fails to ignite and is removed from the game
2-5 The mine detonates, work out damage as normal
6 The mine explodes but only succeed in setting the wall section on fire forcing the defenders to abandon the ramparts. The Skaven models must move either down to the courtyard or to the adjacent towers or walls. If the mine was deployed in the trenchsystem any barricade within 2" is set on fire and must be abandoned by its Skaven defenders. The unit falls back D6" toward the nearest ambush hole, but they are not fleeing and may move and fight normally.

Points cost: 50 pts per mine, one use only. You must note the location of each mine on a map.

Punji sticks
A hole has been dug in the ground and lined with sharp sticks. The hole has then been covered and any model that steps into the hole will have his leg pierced by the sticks. Often several holes are built near each other to catch a whole unit. When the unit touches the area with holes it receives D6 S3 hits with no armour saves. The punji sticks area may be deployed anywhere within the broken ground, including the trenchsystem, and before or after a gate. The attacker can easily fill the holes or knock the sticks over sideways once they are revealed so the Punki sticks are one use only. You can link several areas of sticks to each other to form a longer length of sticks, but the entire are is removed once its activated. There must be a gap of at least 2" between each are of sticks, unless they are linked together. An area of sticks is assumed to be roughly 1" wide but this is never really used as the units takes damage as soon as they touch the area. You must note the location of the sticks on a map and here is an ASCII example.

|  |___________________|  |
|__|       [sticks]    |__|

Points cost: 25 points per 3" area of holes. You must note the rough location of each area on a map. One use only.

Camoflaged Pit
The Skaven have dug a large pit and camoflaged it. These are often located before or after a gate, usually in a narrow passageway to reduce the chanses of escaping. The pits are often lined with spikes, sharpened sticks, starved rats or something equally dangerous. When a unit moves over a pit roll on the Breakage chart to see if the trap is sprung. If the pit is sprung each model in the unit must roll under its Iniative or fall into the pit and take a S4 hit, armour saves are allowed as normal with no save modification. The unit must spend their next turn reforming as they climb out of the pit, helping comrades up or recovering dropped weapons. The unit get no rank bonus if charged while reforming and may not move, but are free to fight normally if charged. If the trap was sprung the unit is halted in basecontact with the pit, if the pit was not sprung the unit completes the movement it was performing. This means that if an attacking unit declares a charge against a Clanrat unit behind the pit and the pit is sprung the charge is not completed, but if the pit was not sprung then the charge is completed. The Clanrat unit behind the pit must declare its chargereaction before you roll to see if the pit is sprung or not. This may leave the Clanrats in a very bad position if the trap doesn't work.

D6 Breakage chart
1 The cover breaks to early and only a single rank and file model in the front rank falls into the pit.
2-5 The cover breaks as the unit passes over the pit and all models must roll under their Iniative score or fall into the pit as the ground collapses under them
6 The cover fails to break and the unit moves right over the pit unharmed. Note that furter units must test again to see if the cover holds.

A unit deployed right after the pit may charge a unit that fell into the pit, even though the pit is between them, its assumed that they were ready with planks to cover the hole. Once the pit has been revealed, any troops may move over it at half speed as they cover it with planks or logs, or move carefully along its edges. The pit may be deployed anywhere within the broken ground, including the trenchsystem, or before or after a gate. The pit count as being 2*2" in size and you may represent it with a template. However you must leave at least one gate without a pit as that one will be used to move in and out of the castle.

Points cost: Each pit cost 50 points. You must note the rough location of each pit on a map.

Cauldrons
The Skaven uses the standard cauldrons filled with boiling oil but also other unpleasent things to repel pesky besiegers. All rules for cauldrons on page 21 apply.

Plaguestew
Clan Pestilen have created a deadly stew of plagues and diseases. Some of these cause instant death and the whole stew stinks of rot. All models that are hit suffers a wound with no saving throw on the roll of 4+. In addition the unit must pass a panic test or fall back. The plague doesn't affect Daemons or Undead.

Points cost: 25 points per cauldron.

Warpfire
Clan Skryre often use cauldrons filled with the volatile mixture of inflammable chemicals and powdered Warpstone known as warpfire. All models that are hit suffers a S5 hit that causes D3 wounds. No armour save is possible. The warpfire inflicts double wounds on flammable creatures.

Points cost: 30 pts per cauldron.

Ratswarm
There is no shortage of rats around a Skaven settlement. The cauldron is filled with rats but it doesn't cause damage as a normal cauldron. Instead a Ratswarm is placed on each flank of the attacking unit and the swarms will attack in hand-to-hand combat. The swarm count as a unit of their own and will pursue a broken enemy. If more swarms are poured from the cauldron they will form a single swarm. The cauldron is one use only and is bought from the Monster allowance as it is essentially two Ratswarm. The Ratswarms don't count toward the number of halfprice Ratswarms you can buy.

Points cost: 75 pts per cauldron from of the Monster allowance. One use only.