I haven't posted new ideas in a while, creativity juices were lacking... but I had a pretty original idea that actually doesn't need any images!
This idea is the Doppelgänger, one of the robots' new creations, it's a black goo, that when detecting an enemy, it morphs into them...
This enemy could appear at any time on any level, why? Because it would scale based on your robot, are you on a bronze level with only a bow and a leg missing? The Doppelgänger will copy your abilities, including the bow and the missing leg, are you a flawless warrior with all of the upgrades plowing through titanium levels? The Doppelgänger will copy ALL of your upgrades, and you'll basically fight against yourself.
Its AI will also scale based on the tier you are, bronze? It'll have a simple AI; titanium? It will be even better than a MK3 Combat Archer. When using a bow, it will take by default the MK3 CA AI, but without the fancy dodging, depending on the level you are, that means, it doesn't matter in what level you are, and your current status (Upgrades, robot damage, clones), it will always be a challenge, also... an extra evil touch, it will rebuild itself, based around how many clones you had when it copied you! *insert Commentatron's "Muahaha"*
Full name: MKX "Doppelgänger" Reversal Combat Robot