Rain Beaten Towers, Endless Siege Waves, and Quiet Gold Farming, First few waves feel rough in a good way. You barely have enough gold to upgrade anything, enemies keep piling in, and one bad tower choice can ruin the whole run. After a while the build starts coming together though. Better defenses unlock, attack speed improves, and the tower finally stops feeling weak.
Some runs work better when focusing on resource income first, others are easier if you dump everything into damage early. Offline rewards help a bit when progress slows down, and unlocking new upgrade paths gives later rounds more variety. Simple setup overall, but surprisingly easy to keep checking back on.