Subject: my opinion on the cannon/last will combo-Derek J.
i beleive that last will + cannon will work because of the following
 
1 cannon lets you put a monster from the field to the graveyard and do 500 direct damage
 
2 cannon does not say only one  and does not say special summons are exempt
 
3 last will says if a monster of yours goes from the field to the graveyard during the turn this was activated  get a 1500 atk or less monster out and special summon it to the field
 
4 last will does not say only once
 
5 last will specifically says put it on the field by means of special summon once its on the field use cannos effect again because cannons effect does not say end phase end turn change phase or anything
 
6 last will is a special summon so can be used more than once
 
7 the most importnant part it says on last will this effect is active for one turn only meaning the whole turn
 
if im wrong ok this is just my opinion email me at thejoker12@attbi.com