Unique - Spoils of War: Melee autoattacks execute minions below 400 (+100% AD) health. Killing a minion by any means heals yourself and the nearest allied champion for 50 (+1% of your maximum health) health and grants them gold equal to the kill. These effects require a nearby allied champion and consume a charge. Recharges every 30 seconds for a maximum of 4 charges.
Unique - Deadly Phalanx: You shield the target ally for 10% of your maximum health for 4 seconds. After 4 seconds, the shield explodes, dealing magic damage equal to (100% of the target's AD) + (30% of the target's AP), regardless of if the shield remained intact. 60 second cooldown.
Defense > Health Defense > Health Regen Magic > Cooldown Reduction
The Spoils of War passive is triggered no matter what method is used to kill the minion, though the execute can only be triggered with melee autoattacks.
The Deadly Phalanx active can be cast on yourself.
The shield changes colors (from blue to yellow) right before it explodes. As an enemy, you can use this visual indication to avoid the explosion.
On Summoner's Rift, assuming Face of the Mountain's user kills the most valuable minions available, it provides 8.9 gold per 10 seconds to the user and to the lane partner before the 35-minute mark. After 35 minutes, it provides 11.1 gold per 10 to the user and to the lane partner.
On Summoner's Rift, assuming Face of the Mountain's user kills one minion every 30 seconds, it provides 8.33(+0.16% of user maximum health) health regen per 5 seconds to the user and to the lane partner.
Note that the shield is a four second delayed nuke, as well as a shield. Putting this on yourself makes you a better duelist, as well as being invaluable to ADCs, providing an extra shield and a nuke.
You can save the four charges and kill four or more minions, and heal nearby allied champions for around (50+20) per charge. This mass heal can help tremendously in a teamfight.
Unique Passive - Spoils of War: Basic attacks execute minions below 200 health. Killing a minion heals the nearest allied champion for 2% of your maximum health and grants them gold equal to the kill plus 10. This effect requires a nearby allied champion to trigger. Recharges every 30 seconds, up to a maximum of 4 charges.
Unique Passive - Gold Income: You may only be in possession of 1 Gold Income item.
Unique Active - Deadly Phalanx: Consumes 20% of your current Health to shield target ally for 10% of your maximum Health for 4 seconds. After 4 seconds, an explosion originates from the target dealing 10% of your maximum health as magic damage in an area. The shield does not need to persist for the explosion to occur. 60 second cooldown.