Start game, then bring down the console by pressing ~ aka tilde or ', 
then enter the code from below for the desired effect. 

gamestop - Units gets 10% cheaper (only works in campaign mode)
oliphaunt - Elephants gets 40% bigger (only works in campaign mode)
Jericho - Walls fall down in a seige (only in Battle map mode)
add_money 20000 - Increase money by 20,000*

* - You must do this on the campaign map, and can only be done once per game. 
After the first time, you must save, quit, and restart the game to use it again. 

Stand off:
When you are outnumbered, have low forces, and know that you will lose, get a 
good stand off position by gathering all of your remaining forces, and go to a hill 
or the highest position if possible. If that is unavailable, go into the forests. Then, 
gather your forces and put all archers in the very back, all medium to close 
ranged missile weapons in middle, and all of your spearmen in the front with the 
legionnaires, swordsmen, etc. just behind. If you have elephants or horses, put 
them javelins. Then, with the spearmen formation, you can either wait for the 
enemy to hit the spearmen then charge with horses. However it would be better to 
horse charge them when they are in archer or javelin range, then keep 
bombarding them. Next, use all of your swordsmen to attack after the enemy hits 
the spearmen. Then, use all of your forces to charge, except for the archers. Move 
them away from the fight and keep bombarding. This is also a good choke point 
defensive maneuver.



Here are ALL the console (key [~]) commands for cheaters and modders :
NOTE: these commands are recognized ONLY in different specific game areas           

? : retrieves help for the command 

bestbuy : sells units cheaper

toggle_tow : shows/hides the tabbed output window

add_money   : adds an amount of money 
to a faction's coffers, can be negative, default is player faction
       
add_population   : adds an amount of 
population to a settlement, can be negative

move_character  , : moves named character to position 
on campaign map
       
auto_win  : the attacker or defender wins the 
next auto-resolved battle

create_unit    
 : creates one or more units of the specified type
  
toggle_fow : toggles the fog of war on or off
toggle_restrictcam : toggles camera restrictions on or off

give_ancillary   : gives the character an
ancillary

give_trait    : gives the character a
trait at level (default = level 1)
       
process_cq  : completes all (possible) construction pending in queue
  
character_reset : resets the character back to it's start of turn settings
  
show_cursorstat : shows the cursor position and region id
  
toggle_terrain  : toggles the terrain to display various data sets, no param
resets to normal
     
give_trait_points    : gives the character
points for trait
       
list_traits : lists all the available traits
  
list_ancillaries : lists all the available ancillaries
  
mp   : gives the character movement points
  
list_characters  : lists all the characters in the world or
those belonging to a faction
       
show_landings  : shows the landing positions available
to the ai from a given region, default hides them
       
filter_coastlines : applies filter to world map coastlines
  
toggle_coastlines : toggles strategy map coastline display
  
set_building_health    :
sets health of a building of the specified type (eg core_building)
in a settlement, so that the final health percentage is as specified
       
ai_turn_speed  : sets the maximum speed of turn processing during
the ai round
       
amdb_min, amdb_max : sets aerial map overlay depth bias for min, max zoom

amdb_offset : sets aerial map overlay offset towards camera

zoom : zooms to specified aerial map zoom

set_ranking_interval : sets the denominator of the faction ranking graph 
interval which is calculated as (number_of_turns / denominator) ;
if set to 0, then the denominator will be set to number_of_turns,
giving an interval of 1
     
regenerate_radar : does what it says on the tin

adjust_sea_bed : adjusts whole sea bed to specified height

reload_shaders : reloads all vertex shaders

reload_textures : reloads all textures

toggle_game_update : fire (mt | toggle | reload | int)

toggle_perfect_spy : toggles everyone's spying ability to perfect and infinite
range, and off again
     
building_debug : toggles building debug mode : TAB to toggle view modes, 
RIGHT SHIFT-TAB to reset mode, LEFT SHIFT-TAB to go back modes, G damages 
mouse-over building, P displays plaza
       
reset_display : forces a display_close() ; display_open() display reset cycle

toggle_underlay : ...

toggle_overlay : ...

process_rq  : completes all (possible) recruitment pending in queue

force_diplomacy  : forces the negotiator to accept or
decline a proposition
     
diplomatic_stance    : set the 
diplomatic stance between the two factions

shadow  : ...

ie  : ...
     
invulnerable_general  : makes that named general invulnerable 
in battle
     
test_ancillary_localisation : adds all ancillary to the character info display

perf_times : toggle display of simple performance times of game update vs display

burn_piggies_burn  : ignite all the piggy winks

test_message : test the event message specified in descr_event_enums.txt

show_terrain_lines  : display defensive terrain features

message_collation_set : set the message collation on or off (sets all factions)

show_all_messages : show all messages to all factions (on/off)

clear_messages : clear all the current stacked messages

puppify_my_love : mmmkay...

reapply_rigid_model_influence : ...

toggle_flowing_water : toggles display of campaign map flowing water

nw_stats : toggles display of network stats

toggle_pr : toggles pr mode

list_units  : lists all of the units in an army

victory   : show victory message for faction for short or long
campaign
     
trigger_advice : triggers an advice

damage_wall    : damage wall of settlement ; 
forces 40% damage to a random gatehouse and a nearby straight section ; 
destroys gatehouse if 'gate' parameter present ; breaches wall if 'breach' 
present
     
test_victory_scroll   : opens up
the victory scroll declaring that the given faction is the victor
     
date  : changes the campaign date to the given year

season  : changes the campaign season to the given season

upgrade_effect  : triggers unit upgrade effect

force_battle_victory : forces the local player's alliance to win the battle,
completely destroying the enemy alliance
     
force_battle_defeat : forces the local player's alliance to win the battle,
completely destroying the enemy alliance
     
output_unit_positions  : output the positions of all units in the
battle to the specified file
     
show_battle_paths : show all valid processed paths in the pathfinder

show_battle_paths_for_unit   : show all valid processed paths
in the pathfinder for a specific unit given a unit id
     
show_battle_street_plan : show the street plan for the settlement

show_battle_marker    : display a marker at (x, y) for t seconds

show_battle_circle     : display a circle at (x, y) of r radius
for t seconds
     
kill_faction  : removes the faction from the game

diplomacy_mission   
 : creates a diplomacy mission
     
event   : creates an event at position

kill_character  : kills a character with the given name

control  : switches player control to specified faction ; 
old faction may not act correctly as ai faction
     
create_building   : creates a building 
of the specified type in a settlement ; for building level see 
export_descr_building.txt.create_building.failed to build building
     
capture_settlement  : evicts any resident characters and 
armies and gives the settlement to the local player
     
disable_ai : disables the ai, so that it does nothing

halt_ai  : halts the turn sequence just before the 
start of the specified faction's turn, or the current faction if no 
faction given
     
run_ai : re-starts an ai turn sequence after disable_ai or halt_ai has been
triggered

Blockades:
If the Senate asks you blockade a port, you can go blockade it for the last turn 
and not have to do it for the entire five.

Defend your settlement:
Use the following tactic to fight an outnumbered foe at your settlement. If you 
know that you cannot defend your walls because there is too much ground to 
cover and you forces will be to thin to stop them, then follow this strategy. Put all 
your armies in the central plaza of the city. According to their location, put your 
light infantry blocking the path of where they would go after the walls break 
through. Remember that you want to make a small chokepoint so that they can 
fight only one way and not surround you. Then, put your heavy infantry behind the 
light infantry and put your cavalry on the flanks so that you can attack them at the 
sides. When they attack and are charging at you infantry, order all the infantry 
(including heavy infantry) to charge. Then, have your cavalry cut the enemy's 
retreat and attack their flanks. If this is successful, their front and rear will be 
attacked, allowing you to crush them. Note: This cannot be done against human 
players.