No revenue estimate for GOG — its rating/review counts don't calibrate to sales the way Steam's do. The Steam version is estimated at $1.6K — a different platform, not this one.

Otherwar

OTHERWAR is a surprising mash-up of Tower Defense and Bullet Hell with the charm and classy aesthetic of the timeless pixel art. Embody the role of the defender angel who has been called forth to stem the tide of an encroaching hell horde. It falls upon your halo to plan out the defenses, however your adversaries shall not stand idly as they will blot out the sun with fire just to clip your wings. Yet, you are not defenseless as the angel can smite enemies on his own if need be. Unlike other Tower Defense games, Otherwar's cast of enemies will keep you on your toes as almost every enemy fires a different kind of projectile. From the ever-following eyeballs to slowly approaching wide spider webs and patterns of swirling leaves cast by undead treants. Amidst the chaos of battle, you will also have to be on the look-out for certain enemies such as necromancers, who, if allowed to linger for too long, will raise skeletons from the dead that may overwhelm your defenses. Before each mission you will have a chance to select towers and skills that will aid you in battle. From straight-forward offensive towers to more situational constructs such as slowing fields that will bog down approaching enemies or emplacements that shoot down incoming projectiles. Besides structures, the angel can also upgrade his own skills during the battle and acquire new abilities between missions. Making each of the 9 levels a puzzle for you to solve. Go, Defender! Carry your light into the dark!