Nah, they still not only work differently, but even are fueled by different things. Eclipse is fueled by whatever type of Magic you can get, while Last Aegis is fueled by Remaining Time. It's possible that Last Aegis might be modifiable in a way that would allow for sacrificing remaining time (life) of thousands other people, or even more ? Still it is easier and better to draw out Magic from other people, since they will replenish it eventually, while there is no way to replenish lost/used time (at least there is no easy way).
Originally Posted by paulbee
It's quite interesting to note that some of the most powerful and old magic actually are not fueled by Magic, but by other things (the amount of magic is likely only used to start the process of drawing that something else):
- Last Aegis uses Remaining Time,
- Fairy Glitter uses gathered and concentrated Light,
- Fairy Sphere uses Bonds and Faith,
- probably more (like using fear and the like).
I guess Lucy's comment about the Origin of Magic being the Heart doesn't seem so far away from the truth.