Is it possible to add another race....

Along with keeps the orignal 4(H,O,U,NE)? I would like to add another race, but at the same time keep the other races so that they can be used in MP by whoever wants to use them.

Don' think you can add one to ALL maps, unless your dedicated. But you can do 'off shutes' pretty easy. Give the undead a cost 0, build time 1 building they can build. Trigger an event off the construction of this building, that removes the undead units, and puts in the starting units of your new race. After 30 seconds or whatever, disallow the building of this unit for all players. Such things can be done similarly with all races, or even more then once.

See header!
I dont know much about triggers so is there any way you could write a mini walkthrough but instead of the undead use the nightelves.

First off sapper, he's making it WAY too complicated. Fact of the matter is is that there's no built-in way to do it. The easiest way would be to use the unit editor to design the units and buildings and techtree you want, purely in the unit editor. Leave the triggers alone. Then setup bases on the map that start with each race including your new one. Granted which race/person starts where won't be random like it normally is, but that's as far as you can go without triggers.

If you do decide to include triggers, your best option is design your units/techtree as said before in unit editor, then setup a trigger to wait 10 seconds after the map starts for the player to type, "New race" in which case instead of creating the starting units of whatever type they've picked at the player screen, you create the starting units for your new race.

If you want to go so far as to make it a race selectable from the drop down list when you play a game... -- that's going to require mpq editing and it'll be a sizeable project. Although over time new tools will be released to make things like this easier.

I think what he wanted was a race you could use in a normal game, and 'pick' as it were. With my triggers you could 'pick' your race, and still get a random start location.

You can't add a new race to the selection menu fo reasons that have been previously explained. I think your best bet is to do what data angel says and make the races built into the map although a trigger based selection is workable. Also since any new race is going to need some introduction this is probably best anyway since you can write the storyline in your map. Elves and Chaos Orcs (with demons to replace the non-Orc units) are the easiest most obvious ones to do both from a storyline point of view and what you actually have to work with in terms of graphics, etc. in the basic game. I plan to make some maps using them myself.

Bah!!
Why don't u guys just edit Slks?????
It's easier for the experienced ones!

i want to remove every race except night elf then add a corrupted version of the night elf.

I dont think you can have custom races and have the original races at same time.

I would make the new race(s) in the unit editor then have a small closed off area like in bottom right or something and let the people pick their race with a wisp or something.

If you guys are so bent on adding another race you might want to try what da said but there's no reason to add another race unless you're in a melee game, and if that's the case then adding another race would be a lot of work. Coming up with your own upgrades and such would not be easy work.

Not to mention making the actual new race balanced evenly with the other 4.

Yes. You can add a new race with replacing any existing ones. You cannot however do it without some serious editing. I have come close but I need to edit the upgrades and a few other things. However since 1.04 has returned full editing capabilities it shouldn't be a problem, just a lot of work.

Basically you'll need to make the new race's units and everything using an enchanced editor. I have gotten this far. The main problem you'll run into here is that whatever race's upgrades your using won't be able to go past Tier 1 since they will be looking for standard town hall buildings and you won't have them. Thus you need to make a new set of upgrades for your race now. This is what I have yet to figure out how to do though I am confidant it can be done.

I did it, made the high elves(very much modified, the original high elves only have a few units, and are not balanced at all) into a 5th race:
I changed all the units I wanted to use, set their abilities, upgrades, etc.
If you originally pick humans, then once the game starts, a dialog pops up, asking which race you want to be. it then either keeps the race you already picked, or replaces the town hall and peasants, with a city hall and elf workers..
I use triggers for unit abilities, and hero limits.

I'm planning on releasing it sometime, once we get it balanced better against the other races..

Making another race is easy.
Making a good one is hard.
As, say making one which doesn't use the traditional Town Hall, Keep, Castle is easy.
I made a map with 6 races via this way.