Earn and spend Runes
You earn Runes at the end of a run, whether you win or lose. Wins award more. Spend them on the skill tree between runs to improve future attempts. Nodes can unlock towers, units, stat upgrades, or new options in the Runestone pool.
Choose and reroll Runestones
Runestones change your current run. Related upgrades belong to the same family, and a run gives you a limited number of rerolls. If an offer already helps the units or towers you are using, you can take it and keep a reroll for a later choice.
When a skill tree node says Maxed
Read the node’s tier description to see what you unlocked. In the 0.19.4e demo, Bovine Cavalry I adds the Pikeman Unlock Runestone to the pool. Look for that Runestone among the offers during a run. Bovine Cavalry II unlocks the Pikeman permanently.
When the Runestone panel stays open
If the panel still covers the map after you choose a Runestone, check whether the wave counter moves on. In one case in the October demo, the panel stayed visible into the next wave and disappeared later. If you decide to close and reopen the demo, expect to start a fresh run. Your between-run progress and unlocks are saved.