More than 600 kilometres from Darwin, in the remote East Arnhem Land community of Nhulunbuy, 130 US Marines, Australian Defence Force and Indonesian military personnel have this week played a rather extravagant game of pretend.
They're responding to 'Tropical Cyclone Sophia' in the fictional nation of 'Belesia'.
The three militaries have been deployed to assist a made-up community left with no running water, cut-off roads, unusable airstrips, and displaced locals, as part of training exercise, Crocodile Response.
"Under the exercise, a cyclone's hit and there's been some fairly widespread damage," Major Tim Murphy from the Australian Army said.
"[There's been] damage to the hospital system, damage to the freshwater supply for the township and damage to the homes and general infrastructure, so under the exercise constraints this is a difficult place for the local population to be living and we're here to help."
This is an annual humanitarian aid training exercise, traditionally involving Darwin-based US Marines and the Australian Army.
Based out of a disused mining camp on the Gove Peninsula, the fictional world is designed specifically for military training, where made-up countries, like Belesia, mimic real ones with their own fictional governments, social issues, and currencies.
The simulation system, Decisive Action Training Environment (DATE), was adopted by the Australian Army from the United States in 2018, and the make-believe training environments and scenarios have been designed to imitate parts of the Middle East and Indo-Pacific regions.
"[The exercise] is quite realistic; we've deliberately used some of the recent experience that we've had in various disasters in the region to build it up into something that gives the soldiers some real training value," Major Tim Murphy said.
For the first time, the 2022 simulation saw 40 Indonesian personnel joining the exercise.
Australian Army Colonel Marcus Constable said the training allowed Indonesia, Australia, and the United States to get a better understanding of each country's capabilities.
"We have, nationally, a comprehensive strategic partnership with the Indonesians [and] there is an opportunity with our close alliance partners, the US, to exercise in a way to develop our confidence and understanding," said Australian Army Colonel Marcus Constable.
The Indonesian Army regularly joins both Australia and the United States in training exercises around the world.
This was the first time the three nations worked together in the Northern Territory, something the Commander of the Darwin-based marines said was "significant."
"We have the opportunity to work with our Indonesian counterparts in Camp Pendleton, where our unit is from, quite frequently but to be forward deployed working with Australians and Indonesians in this environment is quite [significant]," Colonel Christopher Steele said.
United States Marines have been deployed to Darwin each dry season since 2012, with the number of boots on the ground steadily increasing from 200 to around 2000 in 2022.
250 US Army personnel are also based in Darwin this year, as the United States' presence in the Indo-Pacific continues to grow.
Exercise Crocodile Response tested the forces' abilities to assess damage, fix airstrips and generate drinking water direct from the ocean.
Despite the odd language barrier or difference in style, the militaries ultimately said they worked well together.
The biggest challenges, according to US Gunnery Sergeant Joshua Gordon, came from the environment itself when Marines were tasked with creating potable water from the often dangerous shores of the Top End.
"We had to have a Marine on 'croc watch' … to make sure that there was no crocodiles, jellyfish or other type of animals at the water," he said.
"It's such beautiful water and you want to go run in there, but you have signs [and] other ADF personnel that are like 'yeah watch out for the crocs, mate!'"
Just as they would in a real disaster scenario, the Australian Department of Foreign Affairs and Trade staff, as well as their American equivalents, also took part in the training exercise.
Nina Kessler, from the United States Bureau of Humanitarian Assistance, said humanitarian aid deployments are led by civilian organisations, and military troops are deployed to support them.
"Part of what I do is ensure the different military units have an understanding of the authorities, the processes, and best practices the US government would implement when deployed forward," Ms Kessler said.
"The humanitarian response is civilian-led, so to have a civilian face in this type of training exercise ensures there is an understanding of what that civilian interface is."
Planning for exercise Crocodile Response in 2023 is already underway, as the US Marines, Australian Defence Force and Indonesian military prepare for further possible training exercises in the future.
