According to Lewis-Evans the huge success of Fortnite comes down to its appeal to so many different people.
"There's not really any other game out there like it," he says. "It has some Minecraft elements to it and some survival elements to it, and that was in development for a while.
"Then the battle royale mode was added and it's been amazing to see how well that's been received."
The success of Fortnite is nothing like any other game has seen in the past five years, and Lewis-Evans says the Epic Games offices are buzzing about it.
"It's been very humbling and the atmosphere ... is that people are surprised and humbled and want to keep serving our players," he says.
Fortnite fever has also reached Lewis-Evans' hometown of Te Awamutu, where he says it is exciting to watch how involved New Zealanders are with the game.
"It's been great to see how widespread Fortnite has become, especially in New Zealand," he says. "I sent my parents some Fortnite shirts that said 'Developer' on them and they were just swamped with kids wanting to ask questions about the game which is so great for me to see," he says.
Lewis-Evans says Fortnite should be able to remain at the top of the gaming world with the help of his research team.