In order to add some more challenge to the game, when the player creates a clone make the clone of the active robot. Meaning that it has only the upgrades it had when it was created. This will add some thinking to the game because you need to decide whether to instantly create a clone so your safe to die, or wait so your clone will have upgrades to fight the devastating wave (the wave you died on). You could also just make this a setting in the menu. Or an even greater idea, when playing the endless mode have a menu screen that allows you to toggle certain modifiers like the one above, special cloning, and ones like all mark 3 robots, spidertron every wave, all hammers/ all archers/ all swords. These changes is a lot to handle but it would most definitely change the game to be more interesting. If you want to collab on ideas or have any questions, contact me at Bossman20702@gmail.com