[tesco samoa]

for me on average it is 30% or something. I just know it is low enough to release that it is not worth it in relation to other intel attacks such as fake communications, steal resources , plague, etc.... also over looked is the ship bomb... which later in a game when people forget about it... Which is a mistake. Not only does it destroy something on the ship... but it gives you the ship name and location.... So you get a few extra intels right there... But the cost is low so you gotta spend some high point ones in front of it ( if you have lots of intel points...) ( be cool for next game if you could scale how many more points you want to spend to make it really really succeed...)