A new TD...

Me and my friend are making a tower defense. We need something to make it unique (no not different characters or themes, just a special thing to makke it more diverse than other TDs). We will be sure to credit you in the loading screen. Please help!!

Hey, I'd just like to point out that you can't own ideas as nathanmx claimed. Any number of people could have thought that up.

I got some ideas, and I don't care about getting credit:

• Make mazing more interesting; have towers which when placed close together put effects on those moving between them.
• Summoning towers; When a tower kills a unit, a new tower is created at the dead unit's location.
• Don't limit it to a ground-based setting. Air and water works suprisingly well.