Ignore empty fields on join

I have a join call from 3 different tables, the problem is sometimes the field for one table will be empty which will make one of the tables completely unneeded. Since this happens it is calling my database call to fail and return no results.

SELECT villages.name as vname, players.name as pname, tribes.name as tname, tribes.id as tid, players.id as pid, villages.id as vid FROM villages, players, tribes WHERE villages.x = '500' AND villages.y = '500' AND players.ally = tribes.id AND villages.player = players.id"

What happens is sometimes there no "players.ally" to send to "tribes.id" which makes the "tribes.name" and "tribes.id" not needed. Instead of those fields coming back as blank they are completely killing the select.

I have tried:

 SELECT villages.name as vname, players.name as pname, IFNULL(tribes.name, '')as tname, IFNULL(tribes.id, '') as tid, players.id as pid, villages.id as vid FROM villages, players, tribes WHERE villages.x = '500' AND villages.y = '500' AND players.ally = tribes.id AND villages.player = players.id

But the result still comes up empty. Anyone have any suggestions?