To come, to arrive, to make an appearance. Erchomai is one of the most frequent verbs in the NT, used for both ordinary travel and eschatological events. 'The kingdom of God has come' and 'the Son of Man will come again' — same verb, world-changing content.
The entire Christian story is framed by erchomai: Christ came into the world (John 1:9), the kingdom has come near (Mark 1:15), and He will come again in glory (Revelation 22:20). The invitation erchou — 'Come!' — bookends Revelation: the Spirit and the bride say 'Come!' (22:17). Christianity is a religion of divine coming — God moves toward humanity.