People really don't understand the law at all. Disney can only claim damages in any lawsuit if they can show financial loss. If they are not publishing their own pirates game then anything tlopo does can't be cutting into their profits. As long as tlopo doesn't charge money for playing the game, then it falls under the category of "fan fiction". Tlopo can change,anything they want to about the story or game mechanics with no fear of being sued for financial damages. This includes having pirates shoot other pirates with guns....o wait we can already do that.
Minecraft is rated for 7 year olds to play yet it is easily modified to allow players to shoot each other with guns.