Bitcoin Gold (BTG) is a Bitcoin hard fork that took place in 2017. The initial goal behind creation of Bitcoin Gold was to increase level of decentralization of Bitcoin network as it became obvious that most of the network is controlled by few mining pools.
Enjin Coin (ENJ) is an ERC-20 token of the Enjin Coin platform. It’s provided by Binance as part of ENJ/BTC pair. Enjin game development platform provides the tools to create and power blockchain assets.
Zcash (ZEC) is a cryptocurrency with strong cryptography that is supposed to provide high security and privacy. At some point, Zcash was endorsed by Edward Snowden and Roger Ver. Zcash is a Bitcoin fork and it exists since 2016. The mechanism providing privacy is called zero-knowledge proofs (or zk-SNARKS).