Hi.
Some of these spells are very easy to do and you should do them yourself to learn
Others are only possible with advanced mechanics.
In general you should start looking at some tutorials
http://www.hiveworkshop.com/forums/trigger-gui-editor-tutorials-279/ e.g. this
http://www.hiveworkshop.com/forums/trigger-gui-editor-tutorials-279/general-spell-creation-236141/
and also just experiment with the Trigger-Editor.
1. This is easy to do with just one trigger.
Create a Spell, Channel would be good, change the options accordingly in the ObjectEditor and head over to the TriggerEditor.
As Event you can take the Spell event of the spell you just created.
In the Actions you retrieve the target and the caster (Get...) and then apply damage to the target (UnitDamageTarget) and then heal the caster, e.g. with SetUnitLife.
Add (and destroy) Special Effects as needed
2. The wc3 taunt doesn't force you to attack the caster for a duration, it just orders cancel once.
Doing the wc3-like taunt would be similar to the spell above, just in actions you order the target to attack the caster (IssueOrder).
Forcing it to attack for a given duration is hard.
3. As far as I know this is not possible with just ObjectEditing.
Therefore you would need to detect damage-events on your hero, then reduce the dealt damage and calculate & apply damage to the attacker.
Not easy, take a look at this:
http://www.hiveworkshop.com/forums/spells-569/physical-damage-detection-gui-v1-1-0-0-a-231846/
4. Similar to 3., you need to detect damage events and heal the hero for the same amount that damage was dealt.
Additionally here you need to prevent an instant kill by dealing more damage than the hero's max hp.
This is done by increasing the health with a passive skill, healing the hero, then removing the skill again.
5. and 6. I don't know of any target spell that reduces/increases damage taken. Berserk does it, but it's instant cast.
So you would again have to trigger it responding to damage events.
7. This is fairly easy. You could use a modified pocket factory that is just an axe unit, doesn#t produce anything but has immolation with higher range.