Current questions and answers regarding the map editor.

>I broke some heroes using the map editor; with modified parameters, they launch on all maps.

If you change the parameters of built-in heroes in a map, it becomes a mod. To negate this effect, remove the map from the Maps folder if you don't want it to affect other maps.

>And how do you give a hero a permanent army (add a Sylvan to the basic army of the first Lizardman)?

If it's within the map, just give him creatures using a script.

>Add a bite attack.

Again, in this case, the map will become a mod.

GameMechanics\Creature\Creatures\Dungeon (if I'm not mistaken), and look for the creature's xdb file there. At the bottom, there's a list of Abilities; see how it's done for the upgraded Lizardman, and copy the desired ability to the regular one.