Tellurion is a turn-based 4X set in one star system. One turn is one year. You start on 1 January 1960 with one city on your home world, and the game ends after exactly 500 turns, in 2459.
Your first turn
Look at the ground.Each tile has a biome, and the biome sets what it yields. Inspect tiles near your city to find good sites for farms, wells and quarries.
Choose what to build.Open the build palette, pick a building and click a legal tile. Its cost is paid a little each turn while it is built, not all at once.
Read the strip.The resource strip shows stocks and next turn's rate. The forecast uses the same code as the turn itself, so a +4 Food on screen is +4 Food at the end of the turn.
End the turn.Press End Turn when your decisions are made. The turn report then lists what changed, what was finished, and anything that went dark.
The rules that shape everything
Pooled and flowing
Resources come in two kinds. Pooled resources (Food, Water, Ore, Alloy, Credits, Influence and the strategics) carry over from turn to turn, up to a storage cap. Flowing resources (Power, Logistics and Research) are recalculated from zero every turn and can't be saved up. That is why power keeps limiting you at turn 450 just as it did at turn 45.
Every planet keeps its own books
Almost everything is stored per planet. A colony that runs out of water can't draw on your home world's reservoir. Something has to fly the water there. Research and Influence are empire-wide from the start. Credits become one empire-wide treasury once you research Digital Communication, the biggest economic change in the game.
Biomes yield, deposits multiply
What a tile produces depends on its biome. A deposit such as Iron or Timber multiplies a tile that was already producing. Some things never occur on your home world at all: uranium, lithium, ice and sulphur have to be found on other worlds, which is one more reason to reach them.
When you can't pay, things sleep
If a planet can't cover its upkeep, the turn still runs. Buildings go dark one at a time, newest first, until the books balance, and the report names each one. Fix the shortfall and they wake up again.
Earning the sky
The first sixty turns or so happen on one planet. Rocketry gives you your own orbit early. Landing on another world, starting with the moon you can see from turn 1, comes once Propulsion research raises your reach. Each reach era opens a wider band of the system, from the inner worlds out to the gas giants and finally the star's own orbit.
Teaching panels
With the tutorial on (choose Learn to play on the title screen), these notes appear the first time each one matters:
This is your world
around turn 1
This world is your starting point. Inspect the ground, choose what to build, then end the turn when your decisions are banked.
Stocks and rates
around turn 1
Stocks carry between turns; rates are the income and upkeep projected for the next one. Open the report to audit what changed.
What a build costs
around turn 1
A build order reserves its listed instalment. The construction site completes over later turns; the resource strip shows what the next turn can afford.
It is finished, and it starts next turn
around turn 3
The site is finished. Its output and upkeep begin with the next economy pass, so this report records completion before the new rate appears.
Your city grew
around turn 5
Population reached five. Growth adds workers and demand together; the city and resource panels show whether food, water, housing and jobs still balance.
A tech is done
around turn 9
Research unlocks options; it does not place them. Mining unlocks the Iron Mine, but there is no iron on your current world. Survey and expansion reveal where later resources can be worked.
Something is out there
around turn 10
A raider warning marker has appeared. It announces danger before the band arrives, leaving time to prepare units or change what you risk nearby.
Before you attack
around turn ~15
Combat resolves with the turn. The attack panel shows the exact preview and any support you selected; check it before committing the order.
Something went dark
around turn ~29
This structure slept because one of its operating needs was unavailable. Its card and report identify the shortage; restoring the input lets it wake automatically.
The store is full
around turn ~50
A pooled resource reached its cap. More production is discarded until you spend some or raise storage; the highlighted resource explains the cheapest available remedy.
A second city
around turn 17
Your new city has its own population, buildings and local stores. Research and Influence remain empire-wide; most material resources do not move between worlds without freight.
A permanent choice
around turn ~26
A policy card changes how the empire works. Read its ongoing effects before replacing it: political choices can have costs, locks or transition periods.
What is under that tile
around turn ~8
Surveying can reveal deposits hidden beneath known terrain. The ground readout names the best deposit sites; matching extraction buildings benefit from them.
Reading the ground
around turn 1–3
The ground readout separates what is known from what still needs surveying. Traits, site quality and deposits explain why the same building performs differently across tiles.
You cannot go there yet
around turn 1–5
This body is beyond your current reach. Its name, class, reach era and unlock are shown where you clicked. You remain on this world until roughly turn 60; a launch platform changes that.
Somebody else is out there
around turn ~60
Radio contact has revealed another empire. Diplomacy now tracks your relationship, available agreements and what that empire is willing to discuss.
Your troops are hungry
around turn varies
A unit lost strength because its upkeep could not be paid. Restore its supply before more turns pass; the report identifies the shortage and the affected force.
You are winning something
around turn ~150
Your Expansion share has crossed 25%. That is progress, not victory: the standings show the target, current leader and any hold period still required.