Deep Impact challenges multiply the score for endgame impacts heavily. These are pretty varied, but generally speaking, require a high science output for most of them (since there is scoring for levels/variety of built techs of various types, number of age III techs, total actions, levels of blue techs). Overall high economic output is useful as well, since it both helps build all these high level urban buildings and directly leads into impact of balance, agriculture, and industry. You will need a lot of civil actions as well to secure key blue techs, as these are often extremely high-scoring for the investment needed under these rules.

Bill Gates is absolutely excellent for this challenge and generally will be the strongest base game leader since Computers are so good in this challenge, though Einstein can do quite well as well.

Do take care of Impact of Strength, Impact of Culture, and Impact of Science. These impacts can be extremely swingy, especially when multiplied like this. If you don't see them yourself, you may want to try to plan your last turn or two around taking the lead in these.

Remember that you can check the military deck at any time to see all the possible impacts.

Thanks