Suggestions

I tried out the game and its quite good , just hoping for some features  to be added.
1. Able to undo the movements ( For example , I'm suppose to walk to another square but accidentally pressed the wrong one , and i couldn't turn back) (Doesn't apply to after attacking or using a skill)

2. Adding movement points ( For example, it gives out how many blocks a character can move in a turn . If a character is able to walk 3 blocks in a turn , after moving 1 block , the character is able to walk 2 more instead of only giving the choice to attack or using skills on the same turn)

Hi

1.As a strategist you can not undo your decisions! I'll keep this in mind though.

2.Due to how the game it is right now it may be complex to add it.

Does the monster somehow aims for weaker character?
When I put the tanker in front of the line , the monster instead turns around and attack the healer at the behind

Yes the AI does targets weaker chars.

Does the character dissapears completely from the game when they died from a battle?

Yes if they die in battle they're literally dead.

What happens if all the character died? O_O
Game Over? Or the strategist solo it all?

Klein the solo strategist vs the world

The 2016 challenge.

Lol , sounds cool , but I still feel sorry for the people when they died from monsters and restart the battle again to make sure no one dies. Hoping there will be a good ending triggered if i managed to get everyone alive

There are some events that trigger or don't trigger if some characters die. An example is Shime arc and Kamilah being dead, she won't have her lines in her convo. Leaf reacts to it too.