You can identify tables with a huge column count in the following way:
DECLARE @limit INT;
SET @limit = 30; --MAX 30 Columns
;WITH c([object_id], [column count]) AS
(
SELECT [object_id], COUNT(*)
FROM sys.columns
GROUP BY [object_id]
HAVING COUNT(*) @limit
)
SELECT [table] = s.name + N'.' + t.name,
c.[column count]
FROM c
INNER JOIN sys.tables AS t
ON c.[object_id] = t.[object_id]
INNER JOIN sys.schemas AS s
ON t.[schema_id] = s.[schema_id]
ORDER BY c.[column count] DESC;