Problems:

1.For one of my mobs, i'm not using any AITasks, all AI is inside of the actual mob. So his AI is Disabled. It works perfect in eclipse though, but when i reobfustate, recompile and stuff, and putting my mod into the actual minecraft, this mob's AI doesnt work. When i put AI is Enabled, mob's ai stop working too.

2.I think i need to use tasks, but i dont know how to transfer all AI i've got into the task.

 

Could somebody help me with something?

Somebody? Can anybody help, please?

Use 

package fieldgeneral.example.entity.monster;

public EntityYourMob(World world) {
        super(world);
            this.tasks.addTask(TASKID, new AI(this));
        }

I would go in order and have taskid be 1, 2, 3, and soforth

Replace AI with your AI Class

All of this would go in the EntityYOURMOB class