Removes the fog of war
fow
You see every army and fleet on the map. Type the command again and the fog comes back.
These commands change the map and its provinces. The fog of war and terra incognita commands make the whole world visible. Debug mode shows a province's ID and its owner's tag when you move the mouse over it, so you need to turn it on first for the commands that ask for an ID. The assimilate command makes a province entirely yours in a single line, together with its culture and religion.
Most codes here need cheats turned on first. See the section on how to open the console.
cash
Pick the action and type the province ID, and the command is ready.
{action} {province}
To see a province ID, type debug_mode in the console and move the mouse over the province. The default 151 is Constantinople (Istanbul).
fow
You see every army and fleet on the map. Type the command again and the fog comes back.
ti
Toggles the terra incognita layer that covers the regions you have not explored. Used to plan exploration and colonization.
debug_mode
Shows the province ID and country tag when you move the mouse over a province. Turn it on before the commands that ask for an ID.
add_core 151
The province with the ID at the end becomes your core territory, and 151 in the example is Constantinople (Istanbul). If you add a country tag at the end, the core goes to that country.
own 151
The province with the ID at the end becomes yours without a war. If you add a country tag at the end, the province goes to that country.
assimilate 151
Gives you the province's ownership and core and switches its culture and religion to yours. With a single command, the province becomes entirely yours.
colonize <province id>
The uncolonized province with the ID at the end becomes your colony right away, with a core added. According to the Paradox wiki, you also gain some prestige.