Other items will drop but these are of most interest.
Hideous Fungi are the biggest threat with their tough hits and strong summons.
Knights are almost useless here. The only close-combat foes here are Stone Devourer and Humongous Fungus. Hideous fungus and armadiles will mostly ignore knights and focus on mages, making it difficult for a knight to be of any use.
The warzone challenge is a fungus raid, lasting 200 seconds (3.33 minutes). The raid occurs in 10 waves at 20 second intervals. The entire raid spawns about 25 Hideous Fungus and 30 Humongous Fungus.
The warzone challenge is fairly easy in private (i.e. friends-only) teams, except on Hardcore PvP(?). The general strategy is to stack (possible on Optional PvP and dove-mode Open PvP) immediately south of the portal and form a Magic Wall barricade. Only 3 squares need to be blocked if the entire team can stack on 1 tile. The warzone challenge is a bit harder in public teams where players may destroy magic walls (Optional PvP) and push players off the stack. Being the sole target of all fungus will quickly lead to the death of anyone. For this reason during this strategy it is also recommended to avoid fire unless absolutely necessary, as Hideous Fungus will attack players dealing the most damage to them.
Another strategy is to spread the team out to block most of the fungi from spawning.
Finally, one strategy could be to kill the fungi. Each fungus has 4600 or 3400 hp (Hideous and Humongous) and there would be 2-3 of each spawning every 20 seconds. They don't all spawn in vicinity of each other so it is unlikely to work without a very large team.
Note that Hideous and Humorless fungi are distance fighters and retreat at low health. This means that (1) only Humongous Fungus will attempt to block magic walls, and (2) it's a bit harder to clear the waves because the fungi will run.
Deathstrike is the second hardest warzone boss. It is recommended your team have at least 10 shooters to counter his strong heals.