Sigma has been locked away so long working on his own Games that the mention of poisons has barely phased him - such as a toxin that could be used therapeutically, there were plenty of reasons chemists brewed poisons. Sigma, for instance, had brewed his to kill people.

Of course, the current conversation about AIs certainly does help him handwave the morally questionable behavior, as well.

He shook his head in complete amazement. "Hold on. United Planets? What a wondrous world you must come from..." He tilted his head curiously. "What do you mean by your 'team?'"