My friends are apparently getting into Magic: The Gathering and want to turn weekly play into a thing. Which means I'm doing it too. I'm familiar with the rules of Magic and CCGs and general but I have no cards from previous editions and I have not played since Sera Angels and Shivan dragons were OMFG AMAZING cards.

My question is, where do I start? There's the $40 'core' set that comes with some doodads and there's the 'Deck Builder's toolkit' set, and I'm getting conflicting information on where to start. Note that I am largely playing with friends: I have no desire to get into the larger world and find out that I need to spend several hundred dollars before I even start considering being 'competitive.' I just want enough cards to make interesting decisions and play around. Any advice would be appreciated.