Spells

Since i am posting too much, i will ask the spells in here...
1. How do you make a spell get charged by like 25damage per seconds and when released it deals that much charged damage.
Answered

2. how do you make a spell that attacks 5 units in one spell when cast.
Answered

3.(EDITED:12/4 10:19) How do you make the cluster rocket do the exact damage you want to do, can someone make a formula for me plz?
Unanswered

I'm going to give short explanations, since yesterday I gave a really long one and it's time consuming.

1) You're going to want to do this through triggers. The basic idea will be to make a dummy spell that does 0 damage but has the effect you want. When the unit starts casting that ability, turn on a trigger that runs every 1 second of map time that increases a variable to represent spell damage. When the unit finishes casting the ability, select a unit group of units that were hit by the spell, and use the new Unit - Order Unit to Damage Unit action to force the caster to deal the variable amount of damage to each of them. Don't forget to reset the variable damage to 0 at the end of the trigger (I would probably be extra safe, and also set it to 0 when the unit begins casting the ability but most would say this is unnecessary).

2) You probably want to be more specific. Taking a guess at what you mean, you could just use chain lightning and make it so that it jumps 4 times and doesn't lose any damage from jump to jump.

1. Either triggers or use a spell that takes time to cast. I can't think of one right now.

2. Either use Chain Lightning or Forked Lightning as a template. Depending on what you want.