How many words are there using the combination requested?From this list of words that have 'y' in and end with 'ald', you have 4 entries which are available altogether.
What's the highest scoring word in Scrabble available on this page ?4 results possible, you're only feasible choice is 'skybald' for a total score of 17 points.
What's the biggest word you can create using this list?There are 9 letters in the word 'schynbald', which makes it the longest word we have.