Aegis Defenders is a 2D platformer game that combines Metroidvania-style combat with tower defense strategy. The game is set in a world where a ruthless empire has arisen, and ancient technologies mean power. You play as a team of Ruinhunters searching for a legendary weapon known as Aegis that can save their village.

The game takes place in Elam, a dangerous place lost to time, filled with dangerous beasts, forgotten ruins, and powerful relics. The world of Elam is brought to life with uniquely handpainted pixel art style. In Aegis Defenders, players can level up their items and weapons in the shop to take on bigger and badder enemies. The "Fusion Build" system allows players to adjust their strategy on the fly by fusing different combinations of items together to change their defensive setup.

The game features dynamic character swapping, where players need to switch between multiple characters on the battlefield, position them carefully, and utilize their passive abilities effectively to survive. Various tower defense scenarios are available, where players defend moving targets, targets with dynamic abilities like activating doors/weapons, and even targets that don't want to be protected. Aegis Defenders also offers both single-player and split-screen co-op modes, allowing players to enjoy the game together.