WhiteCoin is a cryptocurrency protocol with a Proof-of-Stake (PoS) consensus mechanism. WhiteCoin's (XWC) marketing materials place an emphasis on security and stability, but do not present details regarding their specific technical advantages or project goals.
WhiteCoin's payment network provides a high degree of anonymity and its PoS consensus model allows XWC coin holders to earn revenue by staking their holdings.

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.