How can I list ALL grants a user received?

Following query can be used to get all privileges of one user... Just provide user name in first query and you will get all privileges to that

WITH users AS
 (SELECT 'SCHEMA_USER' usr FROM dual),
Roles AS
 (SELECT granted_role
    FROM dba_role_privs rp
    JOIN users
      ON rp.GRANTEE = users.usr
  UNION
  SELECT granted_role
    FROM role_role_privs
   WHERE role IN (SELECT granted_role
                    FROM dba_role_privs rp
                    JOIN users
                      ON rp.GRANTEE = users.usr)),
tab_privilage AS
 (SELECT OWNER, TABLE_NAME, PRIVILEGE
    FROM role_tab_privs rtp
    JOIN roles r
      ON rtp.role = r.granted_role
  UNION
  SELECT OWNER, TABLE_NAME, PRIVILEGE
    FROM Dba_Tab_Privs dtp
    JOIN Users
      ON dtp.grantee = users.usr),
sys_privileges AS
 (SELECT privilege
    FROM dba_sys_privs dsp
    JOIN users
      ON dsp.grantee = users.usr)
SELECT * FROM tab_privilage ORDER BY owner, table_name
--SELECT * FROM sys_privileges