Cloudspire: Keel – Faction ExpansionExpansion

From BoardGameGeek:

It's All About the Spires Spire placement is always important in Cloudspire, but never more so than for the keel. The keel spires represent the darkness of the keel's void-based technology casting a shadow across the land. As such, spire placement on a tile is the only way a keel unit can transform into its much more powerful promoted version. Some spires even impart new abilities to the promoted minions, creating an even more potent situation for the faction's enemies. But beware! If your minion leaves an island hex with a keel spire on it, it will flip back over to its non-promoted version. To stay mighty, you'll have to maintain a firm hand over the Source wells along your path. Heroes of Ankar The keel also boast some of the game's most dynamic heroes. The faction's starting hero, Chira, has the ability to increase the keel's CP (pending proper spire placement, of course), while the keel leader General Eko counts as a spire in his own right. And don't sleep on Chira, whose Poise ability is a personal favorite in the Chip Theory offices. Poise allows minions to increase or decrease their movement stat, a huge factor in strategic play that can keep your forces more powerful for an extra turn or help them push ahead to a quick victory. -description from the publisher