Crown is a cryptocurrency and development platform with a Proof-of-Work (PoW) consensus mechanism, and an emphasis on community governance. It combines some of the technical capabilities of Bitcoin and Dash. It is currently merge mined with Bitcoin, but is developing a new consensus model called Crown Atomic.

Vertcoin is a cryptocurrency with a strong emphasis on keeping the ecosystem as decentralized as possible. Vertcoin was designed with the goal of being easily mined by all users and to resist the centralizing tendency of specialized mining operations. Vertcoin has a Proof-of-Work (PoW) consensus mechanism that is ASIC resistant, and uses the Lyra2RE mining algorithm.

BitcoinDark is a fork of Bitcoin with a poorly defined purpose and use case. BitcoinDark is based on the InstantDEX protocol, a decentralized exchange for BitcoinDark and other cryptocurrencies supported by the project. The platform is also supposed to include a Pegged Asset Exchange (PAX) to allow users to buy and sell pegged assets – including fiat currencies, commodities, ETFs, and stocks.
BitcoinDark is a Proof-of-Stake (PoS) currency that has gained a significant market cap, but the project has failed to show how its vision will be implemented or how it will add value compared to other blockchain projects.