>Are there any restrictions on certain race/class combinations?
>Like if I wanted to play an elven necromancer would that be
>possible?

The race/class page in Dioxide's has race class combinations tabulated. If there's a number link, the combo exists. Blank boxes mean that that combo is not possible(i.e. no elf necromancers).

http://www.qhcf.net/raceclass.php

>Are there organisations pitted against one another that war on
>a regular basis? What are they?

Cabal vs Cabal wars

Tribunal and Outlander are always at war, with the destruction of the cities Tribunal has been hired to protect being in the agenda of Outlanders.

Outlander and Empire are always at war as Outlanders hate slavery and orderly civilization.

Empire and Scion are always at ar due to historical reasons: The Arcane sect betrayed the old Empire together with lich Valguanera, the founder of Scions, causing it's downfall.

Fortress is always at war with Empire and Scion, as the two cabals are evil.

Battle is always at war against Scion and Nexus, as the two cabals tamper with magic. Nexus actively wages this war only when magic is not too strong.

Battle is more often than not at war with Empire, though they do not need to do so. What fuels this war on Battle's part is the existence of black sect, consisting of anti-paladins and necromancers. The war can also start due to Empire's tendency to gather the items of other cabals, which practically is a declaration of war.

Empire occasionally wars any cabal they see fit, in addition to their normal enemy cabals, Fortress, Scion and Outlander.

Herald cabal does not have item and it's members do not participate in cabal wars. They do not have a cabal item and their headquarters, Inn of Eternal Star, is open for all visitors. There has been one exception, as Imperial High Priest Njaal started a war between Empire and Herald in order to subjugate Heralds under Imperial rule. Imperials were not allowed to enter the Inn during that war. This took place in year 2004.

Cabals vs individuals

-Anything of Evil alignment is an enemy of Fortress.
-Battle ragers generally attack all mages (transmuters, shapeshifters, necromancers, conjurers and anti-paladins) on sight as these are their main enemies.
-WANTED law breakers (see helpfile for laws) are enemies of Blood Tribunal until they are executed.
-Conjurers, Necromancers, Anti-paladins, Paladins, Orcs, Minotaurs, Dwarves and Duergars are enemies of Outlanders, often attacked on sight. This may vary based on individual outlanders, as freedom is important for them.
-Empire attacks whoever they see as an enemy.
-Nexus may attack the characters swaying the Balance. This means that they attack goods if good is in power and evils if evil is in power etc. However, they do not see these people as their permanent enemies, attacking may just be needed at that time to fix the balance.

>Does anyone use a system for combat, and are they widely
>available, if so?

People usually use aliases for longer commands. Personally, I use numpad to move around and put four attack initiation commands to keys 7,9,3 and 1, + and - being up and down and 5 being where. This should be easy to set without further instructions if you use MUSHclient. In addition, many people tend to highlight important echoes, using triggers to colour the trigger phrase echo.