Preconditions

- a city with no territory attached (for cheap attach cost)

- an adjacent outpost (< 45 influence to attach to city)

- an opponent army in the outpost

- no open borders with the opponent

Step 1

- attach the outpost

A trespassing grievance is instantly generated (+5 war score)

Step 2

- demand the grievance (it's a money grievance)

The opponent will most likely refuse the demand, so you need to withdraw or go to war (+10 war score if rejected)

Step 3

- withdraw the demand (+5 war score)

Step 4

- detach the territory for free

Step 5

- go to step 1

Basically you can go from 0 to 100 war support in 1 turn using 225 or less influence. (you get +20 WS for every cycle)

Notes:

- renouncing the grievance will not regenerate it when you reattach. So you only get 5 leverage.

- detaching and reattaching the outpost while the grievance is active will also not generate a new one. (but maybe it should also delete the grievance)

Potential fixes

- the trespassing check should be done at start of turn, not during turn

- or, the game should not generate this grievance multiple times for the same territory in 1 turn (harder to implement correctly)

G17 - Achaemenid Persians Turn 116 - Trespass Exploit.ctr