User summary
ことりファイト! (Birdie Fight) a.k.a. Songbirds is card game about birds trying to achieve dominance in the forest. Each bird is a different color in the game.

Players are forest spirits, trying to secretly guide their chosen bird to success. The cards are numbered 1 to 7 in red, blue, green and white. The players lay a card from their hand to a 5x5 grid after nut tokens (points) are laid out for each row and column.

When the grid is full of cards, the rows and columns are checked. The color with the highest total in a line takes the nut token for that bird. Colors with tied totals are ignored, so a low value card can win the nut token for that bird.

When the nuts are totaled up for the birds, the players reveal their final hand card. That card is the bird they favored (so more than one player might be helping the same bird), and for each player, the number on the card is added to the nut total to identify who has the dominant bird.

Since the players choose which bird they favor by leaving it as their final hand card, they can delay this choice until they see how the game is panning out.

The game rules for the Japanese version, Birdie Fight, come in Japanese and English with the game itself being language free. The Songbirds version of the game is entirely in English. The game includes rules for 2-4 players or a solitaire/co-op mode for 1-2 players.

Japanese version publisher's summary
小鳥たちの勢力争いをテーマにしたゲームです。
各プレイヤーに同数のカードが配られ、色と強さを持ったカードを順に１枚ずつ5×5のエリアに配置していきます。空きがなくなればプレイ終了。縦と横の各ラインで見て、マジョリティを取った小鳥が、そのラインの木の実（点数）を獲得します。各プレイヤーは手札が最後に１枚残るようになっており、それが自分のお気に入りの小鳥となります。お気に入りの小鳥が獲得した点数があなたの点数となります。これを２ラウンド繰り返し、最も点数の高いプレイヤーが勝利します。
英語説明書付き