In Darwinbots there are three primary methods of reproduction. Mitosis, Sexual and Mutational.
As of 2.43.1, .sexrepro allows sexual reproduction in which a bot is produced that combines DNA from two parent bots.
Bots can fire -8 shots which act as sperm and carry the DNA of the bot that shoots them. When a sperm shot impacts another bot, the bot becomes fertilized. The sysvar .fertilized counts down the cycles remaining until the bot is no longer fertilized. If the bot gets shot with another sperm shot while fertilized, that DNA replaces the previous DNA and the .fertilized counter gets set to 10 again.
If a bot sets .sexrepro to a positive value not a multiple of 100 while fertilized, it will sexually reproduce giving the offspring the specified percentage of its resources. The offspring's DNA will be a mixture of the DNA from each parent, constructed with an internal crossover algorithm.