If you want to play without bots you can just skip the plain text and follow the bold text only.
This is a guide on how to LAN Dota 2 when you're at friends etc. and have no internet connection. Normally Dota won't let you LAN only play bot matches solo in offline mode. This is for those people(like me) frustrated that you can't LAN Dota without internet connection.
So to do this you'll need to enable console first by right clicking Dota 2 in steam and selecting "Properties". Then click on "Launch Options" and type in "-console". Click OK and close, you can start the game now and it should take you to something similiar to this screen.
Now type this in the console: "sv_cheats 1" "sv_lan 1" "map dota.bsp"
Once the map loads in the background and you can type in the console again, make a note of the server port in the console here . Your friends will be using this to connect to your game. Now if you want to play with bots type the following in the console: "dota_bot_set_difficulty 3". You can replace the 3 with numbers from 1-3. 1 being easy bots, 3 being hard bots(I am not sure on the difficulty ranking with the numbers maybe it goes from 0-4, 0 being passive and 4 being unfair but I just use 3 all the time anyways which I'm sure are hard bots). Now type "dota_start_ai_game 1". When all this is done, your friends can connect from their consoles by typing in "connect" and your private LAN IP address followed by the port your got earlier. Something like this "connect 192.168.10.12:27015". When your friends are connected, you and them pick Radiant or Dire side by typing in "jointeam good" for Radiant or "jointeam bad" for Dire and "jointeam spec" for spectator. Then close the console using the x at the top right or pressing the keybind for console. Pick heroes and the bots should load in once the game starts. This is a guide for playing All Pick only, if there is a way to play other gameomdes using console then post it in the comments.
Btw I know this is an unnecessarily long and in-depth guide just to type a few commands in the console, but I wanted to make this as noob-friendly as possible. Hopefully this helps some people like it did me. Redtube.vin
EDIT2: credit to /u/Knecht_Ruprecht To select the game mode, you have to type "dota_force_gamemode X" into console before "map dota". X is a number that defines the game mode you will play (Source: http://dota2.gamepedia.com/List_of_Console_Commands
): * All Pick = 1 * Captains Mode = 2 * Random Draft = 3 * Single Draft = 4 * All Random = 5 * INTRO = 6 * Diretide = 7 * Reverse Captains Mode = 8 * Greeviling = 9 * Tutorial = 10 * Mid Only = 11 * Least Played = 12 * Limited Heroes = 13 * Compendium = 14 * Captains Draft = 16 * Balanced Draft = 17 * Ability Draft = 18 * All Random Death Match = 20 * 1 VS 1 Solo-Mid = 21 * All Pick (Ranked) = 22
Edit 2: TLDR(courtesy of /u/gouthamvel :
Here are the list of commands I followed, Scenario: want to play with my friend over lan without internet.
The dota_bot_populate command fills empty slots with bot heros