Lyf How to solve hard/deadly levels? (Part 1)

Hi all,
After having solved 120 deadly levels, I would like to write something of my personally opinion about how to solve hard/deadly levels, for players who feel frustrated on them. Hoping it is somewhat helpful :-)

1.”Freely moveable Objects”(FMO)

Moveable objects are joined by blocks, moveable mirrors and antitanks. Some object is “free”, if it can be moved in a relatively large area. And when one is free, your tank can control it to do many things, such as making a bridge, making a barricade, making up timing tricks, hiding from antitanks, occupying a place on a tunnel and so on. So it is of great value if you have a free object, and even times of value if you have SOME free objects.
It is generally easy to win if you have enough FMOs(except they are too crowded like lasertank.lvl#0250). Then you will know why there are more levels which contain shortcuts in lasertank.lvl file: some authors underestimated the potentialities of the FMOs.
Please cherish your FMOs. Don’t sink one except you have to. Don’t make one unfree except you have to. Sometimes the author make you do some trading: let one go and another come. Trading among FMOs of different kinds is often the key of a level.
“Where will FMOs go?” is often the central problem in the hard/deadly levels.
I take Ch-V#0144 for example. There are 3 FMOs: E2,E5,B7. They are very active and do many things(including many tricks) to show what FMOs can do.

2.Going and Thinking

If you meet a very hard level, only thinking while staring at the origin map is not a very good way. Try to think and GO. Don’t be afraid of failings. GO (while think) and you will be familiar with the map, and get more chances to know what are needed.
I take Ch-III#0003 for example. It is very hard for me and I didn’t know what is the function of the antitanks on the ship during the first hours. I finally decide to shoot them into water then go until I reach a deadend. Then I went on to think what if I bring an FMO or even two to this situation. Gradually I got the idea.
Another example is sok-II#1109. It seems unsolvable then I started to go. Ok I am short of many blocks. Maybe the strategy is wrong. Maybe a beautiful problem has a beautiful strategy. I change a strategy. Wow I am short of 2 blocks. Maybe the strategy is right but I am not efficient enough. Be more efficient. Gotcha!

3. Reversibility

    When can we call a process “from one situation to another” reversible? If an up-pointing antitank is moved left or right, it may be reversible because you may push it back to its beginning place. If an up-pointing antitank is killed, it is irreversible because you won’t revive it. If you moved up an up-pointing antitank it is irreversible unless there are good tunnels. When a unit of bricks is shot, or a piece of thin ice is walked through, it is irreversible. If you can freely shoot both the left and right(or both up and down) side of a rotary mirror, it is reversible.
Sometimes we keep the map reversible in order to avoid regret after hundreds of moves, or just keep a certain area reversible for some time. If you go into a deadend, you can think if you did some irreversible process which is evitable. Let the thin ice break as late as possible. Be careful if you cannot rotate a mirror by 360 degrees. Carefully shoot bricks near ice/antitank.
I take Ch-IV#1833 for example. Don’t shoot all the bricks because near the end you will use some.

This tutorial is written by Li YiFeng nick lyf.