- One full bitcoin blockchain node BTC
It's optional, you can use list of funded address instead.
When we got it all, we ourself or our slicky-fingered friend shall adopt some program like hashcat/john-the-ripper/etc to put 2048 words into 12 slots randomly (maybe via adopted Electrum client) using our computing powers, also writing down used combination to avoid iterations.
That would reduce efficiency since not all 12 words is valid.
How to restore forgotten or lost seed-phrase
Let the great lottery begins!!!
In other words, you're trying to steal other's Bitcoin.