So I'm working on an RPG map and I'm having troubles making an ability... I have no idea where to start with this...

Here's the goal. The Hero will charge a selected unit, deal small damage (increasing in power per point spent into the ability via leveling up), stunning the target for 1.5 seconds and giving the Hero an increased damage buff for 3 seconds (increasing by 1 second per point spent into the ability via leveling up).

Another thing... When the hero "levels up" I can't figure out how to get it so that you can only put 1 point into your ability once every second level.

Some one help me out here?

This is actually a rather complex ability. Obviously it has multiple steps.

First you need an "Effect - Target" ability. What this ability does depends on when you want the buffs to be started. If you want the 3 second buff to start when you use the ability, you should use a "Set" effect. If not, this will be applied later, and you should use an "Apply Behavior" effect. This will change the unit's movement speed multiplier to 1.5x.

The next step you can do in a couple of different ways. You could make a second weapon. This is what I recommend doing. The above behavior would, along with the 1.5x multiplier, disable the standard weapon and enable this new one. This weapon has a "Set" effect as the effect. This "Set" effect will have 3 effects inside of it. One will be "Remove Behavior", with the first behavior being the behavior. The second will be "Apply Behavior", which will apply the attack speed buff. The last will also be an apply behavior as well, but this will be applied to the target, not caster. It will disable all abilities and movement for 1.5 seconds. Add some cool effects to this, like the stunned model that shows when you use that Spectre ability I can't remember the name of.

The second method is using triggers instead of a second weapon. I wouldn't advise this. There are some other ways, but the way I explained above is probably the easiest.

If you want to have the buff applied when the ability is used instead of on contact of the charge, make the first effect a "Set" and then add both behaviors to it.