Site:
www.synthetix.io
Frontier is a chain-agnostic DeFi aggregation layer.
Nexus (NXS) coin is available on a few exchanges, including Binance. You can purchase NXS for BTC. This coin can be staked or mined and serves as the core cryptocurrency of the decentralized Nexus network.
Paypex (PAYX) is based Ethereum protocol. Mercatox remains the only exchange platform, where the token is listed now (PAYX/BTC and PAYX/ETH pairs).