Not a USM title, but Handelabra Studio’s digital release of Sentinels of the Multiverse is a steal at 99¢ (reg $6.99) as well! The Season One IAP has also been discounted to $19.99 ($5 off).
If digital board games aren’t your thing, then there are also loads of other great games on sale right now as well like Hitman GO and Lara Croft GO for 99¢ each, Lumino City and 80 Days for $1.99 each (60% off) and This War of Mine for $3.99 (~75% off).
15 indie developers have coordinated a massive sale, with each offering a discount of at least 50% off on one of their most popular titles for a limited time. These titles include:
Check out the full list of sale titles below.
Note that App Store prices fluctuate frequently and there can be some propagation delay, so the prices above may not be correct. Always make sure that the price is correct before clicking 'BUY'.