If you are a season ticket holder at another Six Flags does that get you any discount here?

It depends on what level of season pass you have. The lowest tier only gives you access to your park. The higher tiers will get you into any park, and discounts on most items. So, if your pass allows you into magic you should be able to get your discounts

It depends on what pass you have

depending on level.

Yes not much but something is better then nothing.