by Steve496
D1-4, last 6 seasons, percentage of games by faction where digging is advanced twice.Faction%GamesTotal Games
halflings99113114
alchemists885967
swarmlings5054107
dwarves411229
chaosmagicians3865172
witches2563255
cultists1939202
auren16319
mermaids713191
engineers29412
nomads25263
giants2141
darklings00500
fakirs0012
So, to summarize: Halflings and Alchemists, almost always. Swarmlings, Dwarves, and Chaosmagicians lead a pack of increasingly occasional diggers. Engineers, Nomads, and Giants very rarely find it worthwhile. Fakirs and Darklings can't.