Viacoin is an open-source cryptocurrency created in 2014, derived from the Bitcoin protocol that supports embedded consensus with an extended OP_RETURN of 120 bytes. Viacoin has a total supply of 23 million coins and a 24 second block time, which means a transaction speed 25x faster than Bitcoin. Other features include a mining difficulty adjustment algorithm called DarkGravityWave, Scrypt Auxpow and Versionbits to allow for 29 simultaneous Soft Fork changes to be implemented at a time.