When you offer minefield level, they will have the following benefits:
- Your mines will not affect them. When their ships move through one of your minefields, they will not risk hitting a mine. Your web mines will not drain fuel from them.
- If they also offer minefield level to you, overlapping minefields will not explode. With alternative mines-destroy-mines, mines which they lay and which overlap yours will not explode.
- They can not sweep your mines.
- They will see the Id of the controlling planet of your minefields.
- They will see your minefield limit.
- They can lay mines in your identity if MineIdNeedsPermission is enabled. If that option is disabled, anyone can lay mines in your identity, even without alliance.