Mage towers drain rage with their attacks and freeze rage generation with their supershots. I would like to see a spell that converts mage attacks into damage dealing for a short time period.
Call it what you want, but it would turn any mage shot that would otherwise reduce you X% of your health instantly instead of sacrificing rage. Kinda like sacrifice but would not generate any extra rage for the loss of health, it just saves you what rage you had from the mage.
Also, to counter the mage super shot, instead of freezing rage the super shot would be converted into perhaps a poison shot that will drain Y% health over the time your rage would have otherwise been frozen.
There are pluses and minuses to the spell which would definitely add a twist to dragon flying. I am not experienced enough with the finer details to define the proper percentages to make the spell useful and not OP, but it would be something I could definitely want to equip on certain dragons.