The maximum supply of Base Set and Transcendent Set crates are 400,000 each. No more than this amount can be minted, ever.
How can I still buy Base & Transcendent crates?
The only way to buy crates at the moment is from another Serran in trading. Be aware though that any trades discussed in trading are executed at your own risk. Peer-to-peer trades are risky and we really don't recommend doing p2p trading. Especially p2p trades without a middleman are highly risky.