This game can be played using only the mouse. Players must guide a certain number of fleas from one point to another by placing three different items on the map: walls, left slopes and right slopes. The keys 1, 2, and 3 provide a quick way of changing the current item.
Flea Circus' scoring system is simple - 100 points for every flea that reaches the exit plus 1 point for every 0.02 seconds of time bonus remaining when you complete the level.
| Image | Name | Function
|
| Entrance | After the countdown at the start of each level, fleas will pour out the bottom of this item.
|
| Basic Wall | Simply gets in the way of the fleas. One of the three items that can be self-placed.
|
| Slopes | Allows the fleas to climb up and down. There are left slopes and right slopes, which are the other two items that can be self-placed.
|
| Balloon & Landing Pad | A balloon will carry a flea upwards until it hits a landing pad. They are single-use and will not stop until it hits the landing pad, regardless of any obstacles in the way. They are always aligned vertically, and on levels with both Anti-Gravity switches and balloons, the balloons will usually have a landing pad both below and on top of it. If there is no landing pad (for example if it has been destroyed by a bomb), the flea will continue to fly off the level and die.
|
| Spring | When a flea touches the top of a spring, it will fly upwards until it hits another item, then it will fly back down and hit the spring again.
|
| Trapdoor | When a flea touches this item, it opens and the flea falls through. Quite similar to having a recessed wall in its place.
|
| Bomb | When a flea touches this item, any items in the 8 spaces around the bomb will be destroyed, as well as the bomb itself. Does not harm fleas.
|
| Water | Will drown any flea that touches it. Similar to spikes. Always directly above a wall tile, though the bottom of it can be exposed in the level "Anything", and will still kill if touched from the bottom.
|
| Fan | Blows any fleas that are horizontally next to it in the direction that is away from the fan, and holds them onto the nearest item, unless it is a slope, in which case the fleas will climb up the slope and away from the fan's hold. To let the fleas go, put an item between the fan and the fleas. These are never aligned horizontally.
|
| Spider | Eats any flea that goes under it, but touching it from the side is safe. Always directly below a wall tile. A flea that is blown under it by a fan will not be eaten.
|
| Teleporter | Always come in pairs: never more, never less. Will teleport any flea that touches it from one teleporter to another, except if a wall if placed in the way of its destination, in which case it acts like a normal wall. If one teleporter is blown up, the other also acts like a normal wall.
|
| Recessed Wall | Is like an empty square, but items cannot be placed in its space. Also see under Green Switch
|
| Anti-Gravity | If a flea touches it, the gravity is reversed. Every flea flies upwards and every other item works upside-down. Balloons bring fleas downward and springs make fleas fly downward. The Classic level Itch is played almost completely with anti-gravity.
|
| Barrier & Blue Switch | Barriers act exactly like normal walls, but can be removed by blue switches.
|
| One-touch Wall | Act like normal walls, but disappears if a flea touches its side. The flea that touches it will bounce off and move in the opposite direction after destroying it.
|
| Bridge | Allows a flea to walk over them like walls, but disappears after 1 flea walks over it. The rest of the fleas fall through. Act exactly like walls if touched from the side or bottom.
|
| Green Switch | Turns all recessed walls in the level into normal walls. Any flea in a recessed wall will be crushed to death in the process.
|
| Spikes | Skewers any flea that touches it from above or the sides. Acts like a wall if touched from the bottom.
|
| Exit | Any flea that touches it is "saved". The objective of each level is to save a certain amount of fleas. Cannot be entered from the bottom if you are playing the old version of the game.
|
| Image | Name | Requirement | Orb Points | Orb Coins | Members
|
| AC | | Circus Act | Complete the first twenty levels of either set.
| 300
| 3
| No
|
| AD | | Circus Master | Complete all levels of both sets
| 1000
| 10
| Yes
|
| AB | | Circus Performer | Complete the first ten levels of either set
| 200
| 2
| No
|
| AI | | Flea Lunch | Save all fleas on level 4 of the classic set
| 300
| 3
| No
|
| AK | | Flea over troubled waters | Complete level 12 of the New set without any fleas drowning
| 200
| 2
| No
|
| AO | | Flea thinker | Complete the first twenty levels of either set without restarting
| 500
| 5
| No
|
| AA | | Flea to the Circus | Complete the first five levels of either set
| 100
| 1
| No
|
| AG | | Flea while you still can | Save all fleas on level 2 of the classic set
| 100
| 1
| No
|
| AJ | | Fleadom | Save all fleas on level 5 of the classic set
| 300
| 3
| No
|
| AL | | Frequent flea-er | Get all fleas in the air at the same time on any level
| 200
| 2
| No
|
| AE | | Golden Fleas | Destroy the golden walls on level 'Golden Fleas'
| 200
| 2
| Yes
|
| AH | | Lord of the Fleas | Save all fleas on level 3 of the classic set
| 200
| 2
| No
|
| AF | | Master Flea | Save all fleas on level 1 of the classic set
| 100
| 1
| No
|
| AP | | Philoso-flea | Complete all levels of either set without restarting
| 1000
| 10
| No
|
| AM | | Sensi-flea | Complete the first five levels of either set without restarting
| 200
| 2
| No
|
| AN | | Thought-flea | Complete the first ten levels of either set without restarting
| 300
| 3
| No
|