This repo has two contracts in a .sol file. The feature responds to RNG (Random Number Generation) by blockhash problem and introduce a contract Hacker that exploits the vulnerability. We mention the possibility to RNG by Chainlink VRF Contract, you can see more in the next link: https://blog.chain.link/chainlink-vrf-now-live-on-ethereum-mainnet/
Video for Spanish-Speakers->https://drive.google.com/file/d/1Br55I1Y518KSoeBPPpV0kDJdFBwAhwHQ/view?usp=sharing