So, thought experiment: weaponizing Dimension Door. No save, no SR, and there are clauses to deal 1d6/3d6/7d6 damage to every traveler (that means you and your target in our case) if there's no room for you right at your destination/100 feet from it/1000 feet from it. Not amazing, but sufficiently fun.
The concept: attempt to take your enemy 1001 feet down, from a ground level. Unless there are tunnels below you, that means damage and no teleportation.
The issue: you take the damage too. That is not efficient in any way.
The solution: is there a way or spell or something to make you immune to (untyped) damage for the shortest of times, like until your turn's end or your next turn?
Bonus credit: any ways to score the 7d6 without a chance of endig with your enemy in an underground pocket?