> For the complete documentation index, see [llms.txt](https://orbcity.gitbook.io/orbcity/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://orbcity.gitbook.io/orbcity/building/construction-system/chance-of-construction.md).

# Chance of construction

| Tier      | common | rare | epic | unique | legendary |
| --------- | ------ | ---- | ---- | ------ | --------- |
| common    | 45%    | 0%   | 0%   | 0%     | 0%        |
| rare      | 84%    | 15%  | 1%   | 0%     | 0%        |
| epic      | 29%    | 45%  | 25%  | 1%     | 0%        |
| unique    | 14%    | 40%  | 20%  | 25%    | 1%        |
| legendary | 0%     | 0%   | 25%  | 50%    | 25%       |

#### The table above shows the probability of getting a new tier of building when a building owner do construction with Building NFTs.

{% hint style="info" %}
**Note: Please note that all figures are subject to change by governance.**
{% endhint %}