Horse Isle is set in a fictional world wherein players can capture, take care of, train and breed horses. The game offers a number of different horse breeds, mini-games and arena competitions for players to take part in.
Horse Isle 1: The main features of the game included being able to catch wild horses, undertake quests given by non-playable characters to earn money, compete in a number of competitions such as showjumping and racing, and chat with friends using the chat feature. Subscribed players[vague] could also own and build ranches, which increased the number of horses they could own, as well as using features such as wells and training pens to water and train all their horses simultaneously. In 2020, following the end of support for Adobe Flash Player in most browsers and its subsequent demise, Horse Isle 1 became the victim of a number of hacks, with the game's data became highly compromised and eventually unplayable, at which point the game was declared unsustainable and was labelled "end-of-life".
Horse Isle 2: Released in 2010, with a single server supporting migrating players of Horse Isle 1. Horse Isle 2 featured an enlarged version of the original map, introducing many new 'isles' and towns for players to visit. Several elements of the original game were retained, including the ability to find and catch wild horses, quests given by NPCs, mining for valuable gems, and puzzles and riddles scattered around the world for players to complete. As of October 2020, the game remains up and running, but is no longer updated.