I just beat the single-player AI handily using the following system:

1. With all robots that can attack the kernel, attack the kernel.
2. With all robots that cannot attack the kernel, move toward attacking the kernel, starting with those closest to the kernel.
3. (Theoretically, if a robot can neither attack the enemy kernel nor move toward it, attack any nearby enemy robots. But this situation never occurred and I still won, so a hypothetical bot built on this system could skip this step.)
4. While I have enough energy to buy a robot, buy the most expensive robot I can.
5. If I still have energy left, play other cards. If a card allows movement, apply steps 1-3.

The only non-robot card I played was Gust of Wind. In accordance with the spirit of the bot, I moved the closest robot not adjacent to the enemy kernel toward the enemy kernel. The robot in question was Martyr Bot, which has 0 attack, so this was a horrendously bad move. But the Martyr Bot had gained 1 attack somewhere (Mercenary Blacksmith, I think), did one damage with its attack, and landed the killing blow next turn.

My point is this: The system outlined above is very simple and very bad, yet still significantly superior to the existing single-player AI. May I suggest improving the AI?