In the video game Grounded, you play as a human shrunk down to the size of an ant who’s forced to survive the perils of a suburban backyard, including mites, beetles, and mosquitos. But when Obsidian Entertainment was developing the game, it found that one critter, in particular, posed a problem: its elephant-sized spiders were just too scary for what was otherwise a kid-friendly action-adventure romp. The solution was an optional Arachnophobia Mode, which gameplay programmer Brian MacIntosh developed in partnership with the Xbox User Research Lab. The mode gives Grounded’s spiders a more friendly appearance, like two round blobs....