You have tiered bot models and AI.

Why not allow us to spawn in companion bots who target the enemy instead of the player? Maybe at the cost of 1 energy bar, maybe they're temporary and despawn between levels.

How we get companion bots of tier 1, 2, or 3 could be handled in the current upgrade tree.

Or we could earn higher tiers depending on the number and type of bots we slay.

It would be good later on in endless mode when theres not much left to buy

Maybe something like the garbage bot that would fly above ennemies and pull them up for a few seconds leaving them weak it would live longer