in order to improve the eternal coliseum mechanics:
1) make the Sword of Reaping/Shield of Life a special skill (like Rally the Crowd). 10 sec of cool down. The new skill will finish/revive a foe/ally at range on activation.
2) make the Sword of Reaping/Shield of Life appear on random positions (north and south or west and east) (and when I say random is sword can appear at north or south).
3) make portals for the holder. The holder should be able to choose to which point want to be teleported. It makes the artifacts more important and more effective (no time wasted on walking and, of course, no falling damage).
thanks for reading!