Urchins and constables may NOT occupy the same space as each other on any location.

Landing on an urchin. If an urchin finishes its movement in a space occupied by another urchin, the current player must move, or ‘bump’, the other urchin up or down one space (the owner of the other urchin has no choice in the matter). If the bumped urchin then finishes on a space occupied by a further urchin, this further urchin is also bumped - in the same direction as the initial bumped urchin. This chain-reaction process continues until each urchin occupies its own space
(eg. in the example here, grey pays 4 green cubes to move 2 spaces; he must then bump pink either a: down one space into the empty 7 space; or b: up one space into the 5 space, which must then bump white up one space into the empty 4 space).

Landing on a constable. Constables (blue pawns) are never bumped! If an urchin finishes its movement in a space occupied by a constable , the owner of the urchin must move to the space above or below the constable (no additional payment is made for this move). If this new space is occupied by another urchin, this other urchin is bumped in the same direction as the first urchin, and so on until each urchin occupies its own space. (eg. in the example here, cream pays 4 green cubes to move 2 spaces but lands on the constable; he must then move either a: down one space into the empty 2 space; or b: up one space into the 0 space, which bumps brown off the top of the location - but NOT back to Fagin.). If an urchin is bumped onto a space occupied by a constable, the urchin skips past the constable into the next space - bumping as it goes!

As a result of all this bumping, urchins may (as we have seen) get forced off a location. These urchins MUST return to their own players for use again. They may NOT return to Fagin.

NB: When a player enters an urchin at the “start” (5) level, all bumping rules apply.