Some parallel worlds have different time-flows, like the fabled dwelling-places of the elves: those who visit them under the hill for a night return to find that years have passed in this world. Perhaps it is the gate leading between the worlds which causes the alteration. If a gate were 'misaligned', the shift from '| |' to '| \' or '| /' as it were would lead to that difference, much as a light-beam split and bent by a prism ends up taking a longer path. There might even be a mathematical function linking degree of misalignment to alteration of time-rate.
From an episode of Justice League Unlimited:
The God of War creates a giant, unstoppable robot (golem, animated armor, etc.) as a weapon for one side in a civil war; his purpose is to prolong the war and create suffering and war among humanity.
Quote from Ares in that episode, which would go well with this idea: "That's all you mortals are good for! To fight and fight and fight until there is nothing left but charred land and blood and bones, and to end it all and then start again with the next generation!"