At random intervals a war breaks out in the Grim Vale area of Croatoa. The Fir Bolg and Cabal are on one side, against their ancient enemies the Tuatha de Dannan and Red Caps. Large numbers of both groups spawn at opposite ends of the vale in several waves and rush towards each other, intent on wiping each other out. There are 3 - 4 waves total, and on the final wave the two giant monsters, Eochai and Jack in Irons spawn to fight each other.
The war spawns for each side are generally fairly evenly matched. But given that the Vale is normally populated by large numbers of Cabal bosses, the Fir Bolg/Cabal side generally has a distinct advantage in the war once the native spawns enter the fight. This usually results in the Tuatha de Dannan/Red Caps side of the war spawn being defeated, while a large portion of the Cabal/Fir Bolg side is left intact. This has the effect of stalling the war, since most or all of one wave has to be eliminated before the next wave can spawn.
This results in the common ability for players to catch the war in this stalled state, and help it along by clearing out the vale themselves of all combatants. This will unstick the war and allow the next wave to spawn. If this is repeated by clearing out each new wave of the war spawn, players can in essence force the spawn of the two giant monsters, allowing players to then defeat the monsters.
If the war is not currently active, however, there is nothing a player can do to start it. There is a 25% chance of the war starting every one to two hours. 
Identifying whether the war is active is often as easy as seeing if there are Fir Bolg spawns in the vale. Fir Bolg are not part of the native spawns for the vale, only Cabal and Red Caps. If there are Fir Bolg present in the vale, they are almost certainly left over from a war spawn. Rarely they are left over from the final wave of the war. But much, much more commonly they are from one of the earlier waves, and are thus an indicator that the player may be able to force the spawn of the two giant monsters with a little work.
The Giant Monster changes introduced in Issue 7, especially the increased regeneration, had a major impact on this event. Previously, Eochai and Jack in Irons were perfectly capable of killing each other. After the regeneration increases, neither of them does enough damage to the other to overcome the other's regeneration rate. This will result in them pounding on each other indefinitely.
The problem comes in with how the badges are awarded. Badges are credited to the player/team who does 10% or more of the total damage inflicted on the enemy, not 10% of the enemy's maximum hit points. If another group (or monster) has been inflicting damage to the enemy for a period of time, they can do enough damage that the team that comes in later and quickly takes down the enemy will find that they did not actually do over 10% of the total damage, and will not get the badge.
As an example, imagine if Jack has 1,000 HP maximum. Jack and Eochai pound on each other for a while, regenerating faster than they are damaged. By the time the players arrive, Eochai has done over 20,000 damage to Jack. At this point, the players will need to do over 2,000 damage to an enemy with only 1,000 HP. Not impossible, but if the players are efficient it's quite likely that Jack will die before the team does that 2,000 damage. And it gets worse the longer the two monsters pound on each other.
In the end, there have been numerous reports since Issue 7 of the two monsters being spotted fighting each other. Teams form, and take them down, only to get no badges because of the situation described above.
- Defeating Eochai will award the Pumpkin King Badge
| Pumpkin King|
The king is dead. Long live the king!
- Defeating Jack in Irons will award the Giant Killer Badge