If the player sides with the UFLL in the climax of Act I and kills Kouassi, Nick Greaves will assume the command of APR troops in Leboa-Sako, leading them out to Sefapane, away from the UFLL's advance.
If the player sides with Doctor Gakumba at the end of Act I, killing Prosper Kouassi as the result, it will be Greaves who finds the player hiding in the desert shelter and then assigns him with assassinating Gakumba at the troop rally. After wiping out Gakumba, the player and Greaves meet up in Sefapane. There Greaves tells that the assassination of both Kouassi and Gakumba prompted Tambossa and Mbantuwe to broker a truce - which, he fears, can result in all foreign mercenaries, including him, being left without any job, and then being terminated. That is why he orders the player to get the Jackal's barge full of guns from the island on Lake Segolo directly into Mosate Selao while sailing under the UFLL flag. By Greaves's estimation, this action would surely reignite the conflict in the area and lead to him taking up the position of Second-In-Command within the APR. When the player successfully performs the operation, Nick Greaves introduces him to Major Oliver Tambossa. The two then brief the player on all faction missions at the APR HQ in Port Selao.
If the player chooses to act as Addi Mbantuwe's representative in the climax of Act II, which is followed by The Jackal assassinating Oliver Tambossa at Dogon Sediko, Nick Greaves - now the new leader of the APR - will contact the player after he escapes from the Falcon Prison and will assign him with eliminating Addi Mbantuwe, who has by then retreated to the Bowaseko Brewing Company office.
After both Oliver Tambossa's and Addi Mbantuwe's assassinations, the player will be approached by one of the two APR lieutenants (either Arturo Quiepo or Walton Purefoy), who will ask to aid him in seizing control over the faction - and that involves assassinating both Nick Greaves and the other lieutenant, who Nick Greaves selects to serve as his aide, during their reconnaissance mission in Sepoko. The player has the option to spare Nick Greaves at this point, and use his help to kill the lieutenant who hired the player instead.
Even if Nick Greaves has been spared at Sepoko, he will still have to be killed by the player at the end of Act III in the Jungle Bivouac.
Nick Greaves is an excellent tactician and is good at strategy planning. He is decisive when the time comes to make difficult choices, often making decisions which otherwise could have not been made by many - like assuming the command of the faction troops when Leon Gakumba began encroaching on the APR positions in Leboa-Sako following Prosper Kouassi's death or eliminating Mbantuwe in order to strengthen his own faction's position in the war.
Unlike any other foreign mercenary, Greaves is concerned about the country's population and their suffering. At some point, he even questions Tambossa's way of fighting the war: making actions which result in additional suffering of innocent civilians. He expresses grief over people sending their money in order to help the country's children, only for the funds to end up in the hands of the warlords. While concerned about the people, however, Greaves is against ending the war, as peace between the factions can possibly result in him and all other foreign mercenaries being terminated.
Nick Greaves treats the player not as a simple mercenary, but as a companion who can be trusted with difficult tasks. He is less harsh towards the player than any other of the lieutenants from both factions.
- At one point, Greaves is described by his aide as being a "glorified airline pilot", implying that he may have a background in the Royal Air Force.