question

We specifically designed the store system for this type of behavior. Here's how you would do this:

First, do not put any price on the items in the catalog. If you do, that price is valid for any purchase call that doesn't specify a store.

Next, set up your store for the "all players" segment (not containing the level 10+ item). We'll call this the "basic store".

Then, set up a store containing the item for level 10+ players. We'll call this the "special store".

In your player segmentation, you'll see that you have an "All Players" segment containing every player in your game. Don't change that one, as you do need it. But you should add a segment for players that have greater than or equal to the EXP you are defining for level 10+ players. We'll call that the "high exp player" segment, for this discussion.

Now, back to the stores:

In the "basic store", scroll down to the segment overrides and set an override to redirect the "high exp player" segment to the "special store". So now, when a player in that level 10+ segment requests the "basic store", they'll get the "special store" instead.

However, a hacker could have the purchase call point directly to the "special store", so the last step is to block them from being able to do that.

Finally, go to the "special store" and scroll down to the overrides. Set an override for the "All Players" segment to redirect them to the "basic store".

The key here is that only one level of redirection is used. So level 10+ players redirected to the "special store" will see that one (they won't be redirected a second time, away from it), but players who aren't can't get to the "special store" by hacking the call, as they're redirected back to the "basic store".