"I fell in love with the cards and bettering myself at the game. Spending the money flew by. I didn't realise how much money I had spent until I looked back and did the math," he said.
Working full time and living with his parents allowed Harrison to fund his hobby.
The most money he'd seen spent on the game was a man forking out $1600 for 12 cards.
"I saw someone pass the guy over the counter $1600 and counting it out in $100 bills. He turned to me and said, 'it becomes worse than meth, mate, don't do it'."
With cards worth up to $400, Harrison said Magic was built on paying to win.
"If you have the money to spend you can definitely come out with a bigger advantage," he said.
"It's definitely a pay-to-win game but that's why they have different game formats and restrictions that really hold people back and give a lot more room for creativity to breathe."
However, since his first burst of paying the big bucks on the game, Harrison now only plays as a hobby.
"I sort of lost all that fire as I got older and couldn't afford as much money as I wanted to on cards," he said.
Franklin Dannis, 20, was introduced to Magic when his friends brought cards to school one day in Year 10.
He has been playing ever since, and said spending money on the trading card game was just like any other hobby.
However, unlike other invested players, he only spent $50 to $200 a year.
"I know people who spend upwards of $1000 to $2000 on some formats in the game and I think it's a little ridiculous."
Hasbro's 2013 fiscal report showed the trading card game has grown substantially in recent years and profits rose 182 per cent between 2009 and 2014.
- Te Waha Nui
