Castles of Mad King Ludwig: Colossal Moats & Barbicans contains enlarged room tiles as well as enlarged Moats and Barbican tiles, tile trays with lids doubling as within-game tile holders, and a score track adjusted to the setup with the larger pieces (as they are not stored on the track in contrast to the standard game). The tiles are twice as big (i.e. four times bigger in area) compared to the standard tiles.
The expansion allows the Castles of Mad King Ludwig: Collector's edition to be played with larger pieces, especially convenient for solo play and conventions. For playing the game, the expansion requires the cards, card trays, and game pieces (player markers, coins, towers, tokens, etc.) of the base game.
The expansion contains two gameplay differences compared to the base game:
1) The Foyer tiles (i.e. the starting tile for each player) of the base game have three entrances at both sides of the tiles. The Foyer tiles of the "Colossal Moats & Barbican" expansion have three entrances on one side and four entrances on the other side, thus allowing more variation in the starting position.
2) The optional Moats & Barbicans module have different Barbican tiles compared to the base game: In the base game, the Barbican tiles are dual-layered and overlap the Foyer pieces such that each Barbican always has an external drawbridge entrance. In the Colossal expansion, the Barbican tiles do not overlap the Foyer tiles and thus allow a Barbican without an external entrance (depending on the orientation of the adjacent Foyer tile), again allowing for more variation in the starting position compared to the base game.
This expansion was available as a bundle with Castles of Mad King Ludwig: Royal Collector's Edition in the Kickstarter campaign.
158 Colossal Rooms
7 Colossal Stairs
11 Colossal Hallways
15 Colossal Secret Passages
10 Colossal Moats
5 Colossal Barbicans
1 Mountain Scoreboard
7 Game Trayz