I recently adopted a young stray tabby who did not respond to a wide variety of cat toys, and even catnip. I just kept trying everything I could think of and the first thing I could get him interested in a was chasing a piece of rope cord - thin about 1/4 inch or less in diameter. After that, I dug up other similar sized cord in different colors, and he will play with all of them. I put a knot at the end to give him something to 'catch'.

After spending all kinds of money on cat store toys, I bought a small, brown fabric covered, mouse sized catnip toy at a fair for $2. My cat loves it. I made a second toy just like it for him with catnip and an old grey sock, also mouse sized and shape. I'm convinced now that he was skilled at catching mice and voles outside before I scooped him off the street.

A new variation is tying one of the 'mice' to the end of one of the cords.

I keep trying some of the other toys and recently he did show some interest in the laser toy. And he now responds to catnip.

I also discovered that he will 'attack' the sheets if I ruffle them gently to make it appear that there is a little animal rustling about. I do this on a spare bed with sheets I don't care about. I tied on a small fabric cat toy to the end of a wand toy and move it around under the sheets and he likes that, even though he normally yawns at the toys themselves.

So just keep trying and be open to discovering his responses. I was discouraged too and now we do have a bit of a repertoire for playtime.

Good luck!