Golden Compass:

The wielder's naval units gain +1 speed and +2 HP This artifact gains 1 charge for every water or coastal tile the owner expands into, and can hold a maximum of 6 (per era) charges At the start of a battle the wielder may the listed charge cost to activate ONE of the following abilities for the duration of the battle. All abilities apply on top of the base speed and HP modifiers: 1 (per era) charges: Naval units gain +1 speed and +2 HP 2 (per era) charges: Naval units suffer -2 speed, but gain +6 hp 3 (per era) charges: Naval units gain +2 speed 0/18