Our first guild attempt on Lake Wintergrasp PvP wasn't horribly successful, mostly due to having a top horde guild with about 50 players on the opposing side. I'm sure there were others, like myself, who had never stepped foot in the area before and didn't really have the 'big picture' of what was going on, what could be done, and what needed to be done. So. Here's a thread for gathering up guides/info/strategies on the Lake Wintergrasp PvP event. If there's interest, I'll put together a guild event for it on one of our non raiding nights.
The following is a partial copy/paste from Wowwiki's Guide to Wintergrasp:
Wintergrasp is a classic "assault"-style gameplay. The objective of the attackers is to capture the keep before time runs out. The objective of the defenders is to keep them from doing so. Should the attackers capture the keep, the battle ends immediately and they gain control.
The objective in Wintergrasp is a large orange sphere located inside the keep itself. The sphere must be activated by a player for 10 seconds, in the same way capturing a flag works in other battlegrounds. If this is done successfully, the attackers win. Any damage caused to a player attempting to activate the relic will cause the activation to stop.
To reach the relic, three levels of walls must be breached. First, the outer perimeter of the keep must be breached. This can be done in any of three different courtyards. The front courtyard is empty, other than NPCs, and the east and west courtyard contain vehicle factories for the defenders. The inner keep walls then must be breached which leads to a courtyard with higher level NPC defenders. The final barrier is the door to the keep itself. Once that is down, the attackers have access to the relic inside.
Each side has access to two vehicle factories exclusive to them. For the defenders, they are located in the keep itself. Portals allow vehicles to teleport out. For the attackers, they are located in between the towers on the southern side of the map. These can be destroyed by the opposing side, using vehicles, and do not appear to respawn. Aside from providing vehicles to the controling team, they also spawn The RP-GG to be used by players to hunt vehicles on foot.
Two capturable factories are located nearer to the keep. They start out under the control of the defenders, but the attackers can capture them. Capturing is done in the form of EoTS nodes, simply have more players standing at the node to capture it. Holding these factories has the dual advantage of allowing vehicles to be built closer to the keep and increasing the total number of vehicles a side is allowed to control. Unlike other factories, these cannot be destroyed.
The keep has towers as part of its design at the corners of walls. The attackers also have three towers at the south of the map. For each of the attacking team's towers that the defenders manage to destroy, the defenders will be rewarded with bonus honor. The towers feature defensive turrets which players can use to fire at enemies. These towers do high AoE damage (up to 5000 for a well aimed shot) and fire quite quickly and thus are quite useful in defense. They can be destroyed by attack with either vehicles or direct attack by players, however they will respawn after some time.
The primary purpose of vehicles is to attack structures such as the keep, vehicle factories, and so on. They can be used to attack other vehicles but are not necessarily that efficient. Vehicles have a large amount of health, but are not particularly armored and thus are vulnerable to basic infantry attack. A player doing a concerted attack on a vehicle can destroy it quicker than the same player attacking from another vehicle.
Attacker Basic Strategy
If you are on offense, your first goal is to take the factories near to the keep. If you have to buy vehicles from the factories in the south, it will take a very long time to reach the keep (vehicles move around regular character running speed). Once you have one or both factories, you want to concentrate on breaching the outer wall. You also may with to fire at the cannons on the wall, as they will do a lot of damage to your vehicle if well aimed. If you break in to the east or west courtyard, destroying the vehicle factory there can be useful, as they can be destroyed. Once you begin to have higher rank players, you should split forces between attacking the keep and attacking players. Siege Engines are the most useful against the keep, and demolishers as well. If you are using a catapult, focus on enemy players and NPCs to try and keep them off your heavier vehicles. Also you can ride along on the vehicles and if they fall under attack, hop off and kill the attacker.
Once the inner keep is breached, all focus needs to go to the relic. Get in there and take it. AoE fears and such to get rid of defenders are useful in here. It is just like a flag capture situation in Arathi Basin.
Defender Basic Strategy
As defenders you need to divide your forces. It is tempting to simply sit in the keep and repel attackers from behind the walls but this is almost certainly doomed to failure. The keep walls aren't that sturdy so even with a heavy defense, you are likely to get breached. Part of the force should stay in the keep and defend it, in particular by manning cannons, the others should go out and assault. If you can keep the attackers from capturing and holding the nearby vehicle factories, you gain a huge strategic advantage. They either need to spend a lot of forces capturing them, or drive vehicles up from the south which is slow.
When you get rank 1 or 2 it can be useful to get a vehicle from the keep and try to strike at the defender's points. If you destroy their southern vehicle points, they then can only purchase vehicles at the norther points and if those are under your side's control, they will have no vehicles. The towers can also be destroyed, but it is unclear what the advantage is at this time.
If the attackers have breached the inner keep, you need to fall back as that's all that matters. It is then just a fight to keep them off it. If you see someone trying to capture it, hit them, and damage will break their attempt. AoEs are extremely useful. You must keep them off until the time expires to win the battle.
Being a world PvP zone, Wintergrasp has the possibility of numbers imbalance between the sides, possibly quite severe. This is countered by a buff called "tenacity" This buff increases the health, regen, healing, and damage of the players that have it. The more the imbalance, the higher the buff. You can very well see cloth characters with 50,000 or more HP in the event of a large imbalance.
If you have tenacity, you need to use it to your advantage. You are more powerful than normal and need to play as such. In particular, acting as basic infantry and attacking an enemy vehicle will lead to it being destroyed very quickly.
If you are facing tenacity, you want to avoid direct conflict with enemy players when possible. Use your numbers to your advantage and focus fire, it'll take multiple people to take one of the enemy out. Remember the buff applies to their vehicles too.