This guide presumes you already know how to use ChallengeEdit (CE), or other CE-based blockmixing programs (like TS). If you don't, google some guides or read the water mixing article I linked above.
To make grass, we need to transform blocks. The first thing you have to do is to add transformable blocks (a block that does not exist yet in your track) to your track. The blocks don't have to be placed the exact same place you want the grass to appear, as you can move them afterward. It is of course faster and easier to place them the exact same place if it's possible for you.
Every image except the CE image can be shown in a big version by clicking the image.
I want to add four grass blocks in the air, so I have placed four transformable blocks where I want the grass. I have chosen the block "StadiumHolePillar" simply because the block hasn't been used in my map yet. Save the track and go to CE.
- The first thing you have to do is to select the primary block. The primary block is the first block you placed of its kind. The primary block is marked with a "-P" as you can see in the screenshot. When you change the primary block's name, all the other blocks of the same kind will also be changed.
- When you have selected the first block (the first StadiumHolePillar in my case), you have to press the "unlock" button. This allows you to change the block type of all StadiumHolePillars. Press OK.
- Step three is to select the block "StadiumGrass" from the block list. Do not use StadiumGrassClip.
- Press "Save block modifications to memory". You will now see that all the blocks of the type you chose, have changed name to "StadiumGrass".
You can now move the grass blocks around if necessary. Save the map. You should now have grass in your track.
Double-mixing
For some reason, mixed grass and/or water will sometimes just disappear from your track after you transform it, but it will still be in the block list in CE. To make the grass/water visible again, simply repeat the process so you have two grass/water blocks on every block. Your grass/water should now be visible again. Sometimes grass/water will disappear from CE as well, if this is the case you have to re-do everything.
Tips and tricks
The back button
Never use it. The back button has an habit to magically unmix stuff. Variation 16 mixes will be lost, grass will disappear and Trackmania will often crash. Never use it. Use the delete button or hide the blocks with CE if they are undeletable.
Fill gaps
Have you ever had a hole into "infinity" on your track? This is caused by many things, and a grass block is the cleanest way to fix this. This will even make cool and new tricks.
Here you see what happens when you mix various blocks to Z=1. Holes.
And here is what happens when you fix it. Pretty nice? All you have to do is place grass blocks in the gaps with Z=0 (you might have to double mix).
Make entire floors
Ever wanted to make a multi-level map? Well now you can. Just add grass blocks to the entire stadium and you have a new floor. You can even start your track on a higher level and then work your way down. This will make some pretty cool mixes too. You can place high blocks underneath the grass and only parts of the blocks will go through the grass. This is limited to Z=0 on the normal grass, but now you can use even higher blocks and other types of blocks. Experiment.
It works above the stadium
Yes, you can blockmix grass blocks above the stadium, but not outside the X or Y coordinates. With creativity you can make some really unique tracks with this method (I have an upcoming map myself with this trick).
Grass is invisible from beneath
This is cool. Why? Well, you can make traps and you can make bugs. Be creative.
