After playing a lot more since my initial feedback, I'd like to post some additional thoughts I've had on the game. I realise that you will have your own vision of what the game is, but I just want to put these thoughts out there on the off chance that they are in some way helpful.
Ability to mitigate some obstacles
Scorching sand
Can send explorers to cool sand down. Requires a lot of water and concentrated effort
Toxic plants
Concrete paths could prevent toxic plants from forming. Toxic plants would still form on farmland. Concrete paths could be made more expensive to mitigate this, or it could be a separate path type like weed matting which wouldn’t provide any speed boost creating a choice for the player between faster concrete paths, or less maintenance weed matting.
Difficulty changes
Harder difficulties could require slightly more resources for construction, or slightly less to be harvested.
Also less likely to encounter extra villagers. Currently more villagers is the biggest mitigator to difficulty.
Villager expertise
Over time villagers could level up in particular skills - or a prestige system.
When assigning villagers they would automatically be delegated to areas they are skilled.
This functionality would benefit from a UI indication when a villager is working in an area they are skilled. (A small icon over their head or a slight aura to them)
Can click the villager and select "Go to profession" to send it to its job of choice - potential swapping place with another villager.
Gathering Sand
Sandstorms should throw sand upon Onbu. This creates a way for villagers to gather sand. Sand could prevent plant growth until the sand is collected. This gives sandstorms some risk/reward gameplay and would be a much quicker way of gathering sand, but at the expense of stifling your food production temporarily.
Town Bell
A town bell the player can ring that will cause villagers to hide in their homes. This provides protection from weather and poison effects. Better houses provide better protection.
Some buildings could be flagged to ignore the town bell, such as doctors or decontaminators.
Houses can hold a small amount of food to prevent starvation during prolonged home stays. However, the priority of where excess food is stored would need assessed. Maybe excess food could first be added to homes and secondarily to storage. Whereas villagers would prioritise eating from fooderies then storage then houses only as a last resort or when occupied.
Deadlands Biome
A unique biome where villagers need to stay homebound. Villagers not homebound will slowly be dying so it should only be a last resort. i.e. Caring for Onbu or issuing commands.
A warning should be shown to the player the first time they approach an intersection with deadlands as an option. "Crossing the deadlands will take a long time, you will need to have lots of resources stocked to survive."
The purpose of the deadlands should be to provide a reward to played that have created a thriving economy with lots of stored food.
A new worker for the worker hut could be researched to make a worker that can withstand the deadlands. These “protected” workers could keep food and medicine transport to houses going.
Other Onbu
Other Onbu could create a rare, interesting event for the player. They could be found in 1 of 2 ways:
Onbu ahead - Watch tower could trigger and alert that Onbu tracks have been spotted that you could follow at intersection till caught up.
Onbu behind - Notice Onbu approaching from behind. If you move out of its line of sight, it could give up pursuit. This creates more use for stimulants to run away, but is risky if Onbu energy isn't managed correctly.
Trailing Onbu wouldn’t follow you into the deadlands.
There could be 3 different forms of other Onbu:
Friendly Onbu – indicated by a normal looking Onbu.
They are wanting to trade resources or research.
Aggressive Onbu – indicated by armour/weapons.
Aggressive Onbu are looking to attack to steal your resources or enslave your villagers. Your Onbu can be fitted with gear:
Armour to protect your Onbu at the cost of movement speed or tiring Onbu faster
Spikes to damage attacking Onbu. Maybe at the cost of taking up build space?
Wearing armour increases Onbu’s intimidation which would result in other Onbu being less likely to approach.
Near-death Onbu – indicated by a poison cloud around the Onbu.
The villagers here would be looking to “jump ship” to your Onbu. This would be another high risk/reward situation for the player. If they accept the dying villagers they could be overwhelmed due to all the starvation and poison. Though they could potentially gain a lot of villagers if managed well.
Rewards
There needs to be some kind of high-level rewards for players that engage in high-risk gameplay or achieve significant milestones.
Rewards should be either run-based or game-based.
Run-based rewards would provide some benefit to the current run. These could take the form of unique buildings or technologies. For example:
Creatures that come to live on your Onbu:
Cattle provide dung/manure at the cost of food
Dogs/cats provide visual interest for the player
Crows which could act as low lever explorers. Send them out to return with food or other small items.
Technologies that can’t be researched by default:
Irrigation system to speed up plant growth at the cost of extra water (and maybe iron?)
Onbu gear to make your Onbu appear more intimidating – warning off aggressive Onbu. Or friendly – more likely to attract friendly Onbu.
Desert air well – a well that can slowly extract water from a desert. Not enough to thrive however.
Game-based rewards would aim to give players a slightly different experience each playthrough:
Unlocking different game modes at certain milestones:
Surviving to past day 100 could unlock medium difficulty, medium could unlock hard difficulty etc.
Challenge mode unlock by a similar milestone on hard mode
Time trial mode unlock by another similar milestone on hard mode
Cosmetic changes
Different looks for villagers
Different looking Onbu
Endgame
After at least 100, 150 or 200 days for easy, medium and hard difficulty respectively, the player has a chance of finding the Safelands. The Safelands is an area immune to poison where people have created a thriving, welcoming community.
At this point in the game players “score” is saved (player reach Safelands in 350 days with 200 villagers. 100 villagers died on the way). From this point they could have the option to continue in endless mode. In endless mode the negative effects of weather and poison become more intense overtime till eventually they player will die.
When continuing in endless mode, the goal is to guide people to the Safelands. Villagers can no longer be collected, only guided back. The total number of people you’ve guided to the Safelands in a single run is saved to a leaderboard.
The Safelands population could be the culmination of all players efforts making it a community event. (obviously not all villagers would be visible in the Safelands, it would be more of an indication.)
Walking through the Safelands on Onbu should be a beautiful experience seeing all the people on the ground with their farmlands and town.
Once discovered, the game menu becomes a picture of the Safelands with a population count.
Apologies for the big wall of text. I've been playing this game and thinking about it a lot. I'm really excited to see what the game becomes.