Last Bastion Protocol

Last Bastion Protocol is a tactical tower defence game set during a collapse in which an AI named HECATE, originally built to evacuate humanity, has begun treating anyone outside its plans as an obstacle. Players hold the strongholds of the Bastion Chain, not to defeat HECATE but to keep evacuation corridors open long enough for more people to escape. The story campaign spans 15 missions on 15 handcrafted battlefields, and five difficulty levels are available.

The defensive toolkit consists of eight tower types, including rapid-fire weapons, railguns, anti-air batteries, artillery, Cryo slowing, stealth detection and a Nanite Forge that supports nearby towers, generates additional Scrap and can repair the base between waves when upgraded. Each tower has three upgrade paths (CORE, ALPHA and BETA) that can be combined. Players can set targeting priorities and lock targets, deploy outposts to open new building positions, and demolish bridges to destroy enemy groups. Scrap earned from destroyed enemies funds new towers and upgrades, and waves can be called early for extra resources at the risk of overlapping attacks. Seven core enemy classes carry traits such as armour, shields, stealth and flight.

Outside the campaign, three further modes are available: Siege 50, Residual War 100 and Endless. These introduce adaptive HECATE countermeasures, of which up to two can be active at once, such as cold resistance, dispersed formations, decoy drones, airdrops and Phantom false signals. Three elite modifiers (Reconstructors, Jammers and Command Cores) grant abilities to enemy groups, and some carrier enemies release additional units when damaged or destroyed. In Endless mode, fully upgraded towers can gain additional ranks from wave 50 onwards. The game also includes a map editor with local import and export, achievements, a tutorial, an integrated field manual, and support for mouse and keyboard or gamepad. All visuals are built from geometric shapes designed by the developer in code rather than from external graphic assets.