> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cromos.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# The series object

> The top level of the catalog.

A series groups the expansions released under one banner: Base, Sword & Shield, Scarlet &
Violet. It is the coarsest way to slice the catalog, and there are around twenty of them.

Ids are short and stable: `base`, `swsh`, `sv`. Fetching one returns its expansions inline,
ordered by release date, which makes a series the natural entry point for a browse.

<ResponseField name="logo" type="object | null">
  `{ low, high }`, or `null` where no logo is available. The two may be the same URL.
</ResponseField>

<ResponseField name="palette" type="string[] | null">
  Up to four dominant colours from the logo, most prominent first, as `#rrggbb`, for gradients and
  accents drawn from the artwork rather than picked by hand. `null` where there is no logo or it
  yields no colour. See [the expansion object](/expansions/object) for the full rules. They are
  identical, and each expansion carries its own.
</ResponseField>

## Example

The Base series carries seven expansions. Trimmed to the first three below, still in
release-date order, to keep the example short.

```json theme={null}
{
  "data": {
    "id": "base",
    "name": "Base",
    "logo": {
      "low": "https://assets.cromos.so/expansions/base1/logo/low.webp",
      "high": "https://assets.cromos.so/expansions/base1/logo/high.webp"
    },
    "palette": ["#fac32c", "#2a2e54", "#6d2239", "#3c5da4"],
    "expansions": [
      {
        "id": "base1",
        "name": "Base Set",
        "logo": {
          "low": "https://assets.cromos.so/expansions/base1/logo/low.webp",
          "high": "https://assets.cromos.so/expansions/base1/logo/high.webp"
        },
        "symbol": null,
        "palette": ["#fac32c", "#2a2e54", "#6d2239", "#3c5da4"],
        "release_date": "1999-01-09",
        "card_count_total": 102
      },
      {
        "id": "base2",
        "name": "Jungle",
        "logo": {
          "low": "https://assets.cromos.so/expansions/base2/logo/low.webp",
          "high": "https://assets.cromos.so/expansions/base2/logo/high.webp"
        },
        "symbol": "https://assets.cromos.so/expansions/base2/symbol/image.webp",
        "palette": ["#010202", "#43ac4b", "#93c562", "#434443"],
        "release_date": "1999-06-16",
        "card_count_total": 64
      },
      {
        "id": "basep",
        "name": "Wizards Black Star Promos",
        "logo": {
          "low": "https://assets.cromos.so/expansions/basep/logo/low.webp",
          "high": "https://assets.cromos.so/expansions/basep/logo/high.webp"
        },
        "symbol": "https://assets.cromos.so/expansions/basep/symbol/image.webp",
        "palette": ["#000000", "#fefefe", "#2c2c2c", "#636363"],
        "release_date": "1999-07-01",
        "card_count_total": 53
      }
    ]
  },
  "error": null
}
```