Anshuman
I think leading by example was a big factor in building that team culture. Another one would be taking responsibility, showing a problem-solving attitude, and never only speaking of a person's shortcomings, but also mentioning them how they can improve/what they're doing great at.
Last but not the least: the fact that the founders actually cared. I think this is another huge factor, you can do everything right but unless you have empathy, we cannot connect. The reason, I still care about us, likewise everyone from Frontastic does, is because we looked up to the founders for their solid character, which you presented in a way that had a positive impact on us.