About This Game
Prismkeep is an idle tower defense that runs in real 3D and is built to be played for weeks rather than minutes. You hold a single keep at the center of the board while enemies close in from every direction, and the numbers underneath — damage, fire rate, gold income, targeting priority — are the actual game. Waves keep coming whether or not you're paying close attention, so it works both as something to focus on and as something to check on.
The long arc is prestige. Run your keep until it falls, cash the run out for permanent cores, and start again stronger — the loop that makes each restart shorter and each ceiling higher.
How to Play
The run starts on its own — there's no menu to clear first. Enemies approach the keep and your defenses fire automatically; your job is deciding what to spend gold on and when. Buy upgrades from the dock to raise damage, fire rate and income, and switch targeting between first and strongest depending on what's coming at you.
Boss waves arrive on a schedule and bring escorts with them. Shielded enemies mitigate part of every hit until their shield is stripped, and splitters break into a brood when killed rather than simply dying. When the keep finally falls, prestige converts the run into permanent cores and the next run begins from a higher floor.
Strategy Tips
- Income upgrades compound and damage upgrades don't — early gold spent on economy is usually worth more by the boss wave than the same gold spent on raw damage.
- Switch targeting to strongest when a boss wave lands and back to first for ordinary waves. Leaving it on one setting all run wastes a free lever.
- Shielded enemies mitigate roughly half of each incoming hit until the shield breaks, so many fast hits strip a shield far more efficiently than one slow heavy one.
- Splitters produce a brood on death — clearing them early, away from the keep, is much cheaper than clearing them plus their offspring at the wall.
- Prestige earlier than feels comfortable. A run pushed well past its efficient point earns very little extra, while a fresh run with more cores rebuilds that ground in a fraction of the time.