- or if you have multiple maps: a lizard would start on let's say a swamp like map and a dward in some dwarf mine like map.
No, all players must be on the same map.
Not entirely true. You could have a map with several level templates within it, inside one bigger level and have an event box around the starting triggers.
Then have an "If CharacterEnteredTrigger" and check if they're a dwarf, lizard, etc, then separate that player from the party and teleport them to their respective level template.