The following mapmaker glitches/exploits apply only to the TimeSplitters Future Perfect Mapmaker.
Indoor weather (all varieties) happens in large stackables, and in small stackables when you stack the alternate stackable (#28 tile) underneath the normal one (#27). This happens both for indoor maps and for outdoor maps in places that should be roofed in and therefore have no rain or snow falling.
If you put a #22 tile (Ramp) in a map and add a door at the bottom, so that downward travel in the ramp is eastward toward the door (to the right on the map grid), going down the ramp will result in falling out of the tile. In multiplayer modes you will fall to your death; in story mode you will land at the bottom of the ramp tile unharmed. This happens in all tile sets; however, since the military ramp is wider, you won't fall completely outside the tile in multiplayer unless you walk against the wall after the glitch point. This "trap" can be circumvented by hugging the wall when you go down the ramp.
Enter bunkers with locked door
Make a corner bunker tile with gaps. Place a locked door on the corner gap, and a window on the side gap. Place a turret inside, next to the window covering a wide space on the properties window. Now activate the turret on the outside, turn and exit the turret. If you did it correct you will be on the inside of the bunker.
In the TSFP mapmaker, place a bunker-corner-gap. Now, place a window in the gap & place a buggy inside that that's facing outwards from the window. Use the map & enter the buggy.
Now, when you accelarate, the window will break & cause sparks to fly out even if you stop or get out, & if you reverse, the same thing happens only you get an extreme close-up of your characters face. The only way you can stop the screeching noise it makes is by quitting the match.
(Note: This was achieved by attempting the previous glitch with a buggy & a window).
Multiple cat control
Make any map, and place two Remote Controlled Cats anywhere in the map (though preferably as close as possible), now, when playing your map, bring the two cats directly next to each other, so that they're practically touching. Now, walk up to them both, and tap the activation button so that you are controlling one of the cats. Now, tap the activation button again, and your view will change to the other cat, now move around, and you will be controlling two cats! (NOTE: This glitch allows for controlling any amount of cats)
Make a map with a buggy, and a fall/drop from any height. Place the buggy on the bottom floor where landing from the fall/drop is possible... or drive it there (bottom can even be a death pit tile). While in the game, jump onto the buggy from above. Rather than landing on the buggy, you will teleport back up to the tile that you just jumped from. If you press the "enter vehicle" button when falling onto the buggy, you can enter the buggy and thus survive a 4-story fall (unless of course the bottom is a death pit tile, in which case you will die upon entering the vehicle).
Merging or Overlapping Tiles
1. Basic Merging of Tiles (2 possible methods)
1.1 Select the two tiles you want to merge. Put one of them on the fifth floor, and the other one below it, on the third. Put a Story AI in either one. On the first floor, somewhere off to the side, put a third tile. Next, mark the top tile and the bottom tile that is off to the side, and grab the bottom tile. Move it up two floors, to the 3rd floor (doing so moves the tile that was on the 5th floor up to the 7th floor). Grab the tile that you just put on the 3rd floor and bring it back to the first floor where it started. Now, mark your tile you originally put on the 3rd floor, and mark your 1st-floor tile again, so that both are highlighted. Now grab your first floor tile again and move it up four floors, to the 5th floor (doing so moves the tile that was on the 3rd floor up to the 7th). Now, open up your Story AIs. Find the one that is now on the 7th floor and select "Show in Map." Once on the 7th floor, drag a select box around the merged tiles where the AI is. Leave these highlighted, then go back down to the 5th floor and mark the tile there. Grab this marked tile and bring it back down to the first floor (doing so will move the two merged tiles on the 7th floor back down to the 3rd floor).
1.2 An alternative way of overlapping/merging can be used that does not involve the 7th floor and Story AI. Place a tile #11 lengthwise along the edge of the map grid, at the very top of the grid (in the first row of the 40 grid rows). Next, place a series of #11's connecting to the first one, moving inwards on the grid towards the bottom. The more #11's placed, the better. They all must connect along their long edges. Now mark all the tiles or drag a select box to highlight them, and move the cursor northwards out of the map grid. The grapple icon of the cursor should be north of the first tile, outside of the grid, as far as you can go outside without losing the "grab" option. Grab the marked tiles and place them again (cursor should remain outside of the grid). When you put the tiles back down, you should see that somewhere along your column of #11's, two of them got overlapped (if not, keep trying; it will happen). Once it happens, delete all the other tiles that didn't get overlapped. You can now drag a select box over your first overlap, to copy/paste for other overlaps. Change which tile in an overlap is tangible/intangible by dragging a select box to highlight both tiles, using "mark" to un-highlight the tangible tile, and picking up some other highlighted tile to make what was once intangible tangible, and vice versa (intangible meaning it can't be touched with the cursor, vs. tangible, which can be touched).
Now that you know how to merge tiles, you can acheive some very cool effects.
2. The Floating Platform
Merge two large open stackables or two small open stackables. Place more stackables on each side of it; this will remove the walls. Before you play it, make sure there are no tiles left on a higher floor somewhere, so that the platform will be the highest tile and therefore without a ceiling. You now have a platform floating out in the open in the middle of the skybox.
3. Windows to the True Outside
For a room with a window view of the sky outside, first create the basic room. Then merge two stackables. Place them bordering the room and place stackables on all sides and above and below the ones you merged. Separate the merged tiles from the room with a window. Now, when you play the map, you can look out a window and see the skybox outside.
A note about merging tiles and tile visibility: Sometimes, when you merge tiles, and are walking through the tile in mapmaker preview, you'll notice tiles adjacent to the merged tiles suddenly disappear from visibility. There is a simple rule to how this works: any tile already placed in the mapmaker will not go invisible, if you connect the open edge of a merged open-edge tile with the edge of the pre-existing tile. If you connect a new tile to the open edge of a merged tile after the merged tile is placed, the new tile will go invisible for a view of the sky box. This is the principle on which the Windows to the True Outside glitch works: placing tiles after the merged tile is placed. If you are not making a Window and have placed adjacent tiles after the merged ones, but do not want them to go invisible, simply grab the tiles you merged (drag a small select box, or a select "line" to grab them), pick them up, and put them back down again. Since you have now placed the merged tiles after the adjacent ones, the adjacent ones will no longer go invisible.
4. Perpetual Blood Machine
Create a military map. Merge a deathtrap tile (#45) with a small open tile containing a spawnpoint in it. Now, whenever you spawn there, you will instantly explode. Note that the deathtrap must be above the other tile (be tangible) when you merge them or it will not work. Death is caused only by the mines in Military's #45 tile. In the other tile sets, the #45 tile will not cause death when merged with another tile.
This glitch works great when making story maps. Have story AI set to spawn and wait 999 times and place them on this tile combination, but place it above the area of the map that you will be using. When playing the map, it will case the surrounding area to shake violently, like it is being bombed.
5. Didn't I Just Come From That Way?
Merge a triple corridor with a small T-Junction, with the T-Junction being tangible and its wall on the edge of the overlap where another tile will connect. When merged, the T-Junction wall will be invisible and passable on one side, and visible and impassible on the other. Players will walk through a corridor and turn around and see a wall blocking the way they just came from.
6. 3-Way Teleport
Place a One-Way send Red Teleport somewhere on a map and a One-Way receive Yellow Teleport elsewhere. Then, merge a One-Way receive Red Teleport with a One-Way send Yellow Teleport. Players will walk into the Red Teleport and emerge somewhere in the level. When they walk back through, they will end up somewhere entirely different from where they started, effectively making a three-way teleport.
7. Sky floor
Merge a normal 3x3 room with a stackable one, then place a further 3x3 stackable room under the merged tiles. The floor will turn to sky, and you will still be able to walk on it.
8. Doors/Windows everywhere
Make a normal 3x3 room "intangible", then place 2 small rooms on it. Put a window between these two rooms, mark the 3x3 room and move it away. The window/door will be glitched into the normal 3x3 room.
Place an "intangible" room and put the open bunker corner on it, then place a window/door where it is supposed to be on the bunker corner. Make the normal 3x3 room tangible and the window/door will be diagonal in the room.
10. Walking on small stackable rooms (Military TS only)
Place an "intangible" trench corner. The stackables you place on the white parts of the trench corner will turn to an "invisible" floor, so that you can walk and shoot through them. Don't forget to place some stackables under the first ones. Its useless otherwise.
11. Flames in tiles (Horror TS only)
A bit more complicated... Place a big deathpit and put (a) random room(s) on the 1st deathpit floor. Put a big room (2 floors - Important!) in front of it. The flames belonging to the deathpit will now be seen in the random room(s). You should place the big room at the end otherwise the glitch will be messed up ...If it happens that some parts of the rooms turn to sky then just replace the big room...finish.
12. One way windows
Make the tile you want to see through "invisible". Place the rooms that will be connected to it later. Now chose a room that has the same size and place it on the "invisible" room. The room which will be added will show you the tile you placed on the 1st one. Try to make a tunnel: -make a small ramp (size:2x1) "invisible" put a small corridor in front of it -after this you have to place a further small corridor but now on the ramp. -place a room on the side where the ramp cant be connected usually, the last room you placed is now connected to the small corridor. -put a window between these two rooms
You will now be able to walk on the ramp like you do it in a normal match but when you go behind the ramp you can shoot on the people walking along the corridor and ramp.