I have some ideas for the game to be that little bit better,
1. Have a mouse option (move the camera/player with the mouse).
2. be able to move the menu options with the arrow keys and press enter to select that option.
3. An option for: Easy mode: Player moves slower, but gains less score.
Medium mode: Player moves normally and gains the . normal amount of score.
Hard mode: Player moves quicker, but gains more score.
4. An option to change the controls e.g. Change left arrow to 'A' and change backspace to 'R'.
This is all I could think of so far, no need to add them they're just suggestions.
This game could be better if there were some sort of currency (Coins etc.) to find in game and spend in a shop where you could increase speed, jump power and other key things. Also what itsmechrisa said was a good idea too.
I dont know if I should count this as a glitch, but once you reach the Black Captain, you can dodge his first move and move all the way to the right of the map and you basically win if you have 2 armor.
This game is really Simple and Effective, But I have one Idea that might Improve the game. You could make it so you Could Throw out Fish you Don't want, Just an Idea. 4/5 So Far
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You can sell at Merchant city, but need to unlock the store first :)