Remember trading cards? For the past few generations, trading cards have been a staple of childhood. At first it was collectible sports cards. Then, a couple decades later it started to be fictional characters like Nintendo’s Pokemon. All along the way, the theme was to not only own more than your friends did (by trading and buying at random), but also to “get ‘em all”. This highly profitable business has now been brought into the 21st century, with a hot startup that is taking off in the UK, Fight My Monster.

Fight My Monster takes the traditional trading cards system, and gives it a splash of interactivity. As I am neither a 12-year-old boy, nor an employee of the company, my trying to explain how it works wouldn’t be fair. So here is Fight My Monster’s Executive Chairman Dylan Collins, “It’s a trading card game. You create your monster cards and then battle with other players to level your card collection up as well as buying and selling with them in the marketplace.”

The company has seen massive growth, with three quarters of a million boys aged 8 to 12. The kicker? That’s all off of a bootstrapped budget of £150,000. However, wanting to expand and grow the company even further, they are now taking a large investment of $2.1 million. The funding round is a seed stage investment, being led by Greycroft Partners with participation from eVenture Capital Partners, and a number of U.S.-based angels.

While most gaming companies now go with the free-to-play model, Fight My Monster is going the more traditional route of subscriptions. This means that the control stays in the hands of parents, and also gives the company a clear monetization strategy (something many startups lack for far too long). The company is looking to use the funding to increase the size of their team, by hiring some “very smart developers”. This will allow them to roll-out planned features faster, and continue to grow at a fast clip.