Castlot is a free to play, browser-based MMORTS game that has a heavy focus on MMORPG elements such as character progression and the equipment system. The game also has an in-depth story to accompany the large number of quests, the majority of these quests are linked using the story which is a fresh approach for the genre. You pledge allegiance to the Dark or Light side, defending your Kingdom from the onslaught of the opposition, Castlot offers many unique features never seen in the RTS genre.

As with most RTS titles, base building is a vital part of Castlot. Players must gather and collect various resources in order to be able to construct various buildings and defensive items. A unique aspect to Castlot's base building system is the free roam placement, players are able to place the buildings anywhere they please and are free to move them whenever they want, at no extra resource cost. This is a nice feature as many games force players to destroy buildings in order to replace them.

The battle system is also quite in-depth compared to other titles in the genre, players are able to select what tactics their units use in combat right down to the direction they attack from. This allows for more direct influence on the outcome of battle, rather than the typical RTS approach of who has the most units wins. The fights themselves are featured in high quality 3D graphics with smooth and artistic animations, when combined with the in-depth storyline, it creates a very immersive experience.

Goblins are also a new feature to the genre, players are able to use their commander to capture and train A.I Goblin units. Fitting in with traditional Goblin lore, they act as spies and thieves, reporting back to you on enemy movements and progress as well as being able to steal various resources and units from your enemies.