Temporal Movement and Dimensional Movement

Super Movement has 2 types of movements that specifically say the GM should highly regulate or ban use of altogether. Temporal Movement and Dimensional Movement. Earlier I spoke about how to make a "Time Traveler" without the Temporal Movement ability per say. But is it possible to have a campaign that allows these movements (which most GMs just ban outright?)

Temporal Movement:
1 rank (2 points): Travel between the present and one fixed point in time (such as 100 years in the past or 1000 years in the future).
2 ranks (4 points): Move to any point in either the past OR the future (and presumably back to the present again).
3 ranks (6 points): To any point in time.

Dimensional Movement:
1 rank (2 points): Between the home dimension and one other dimension.
2 ranks (4 points): Between any of a related group of dimensions (mystical, alien dimensions, etc)
3 ranks (6 points): Any dimension.

By comparison, 2 ranks (4 points) of wall crawling allows you to move at your full movement speed when climbing with no climb check, or to ignore hampered movement, or walk at full speed horizontally on air.

Both of these powers work like teleporting to some degree also, but let's first clarify some of the inherent weaknesses in both. First being that they are NOT teleport.

Travelling between dimensions gets tricky, because the dimensions do not necessarily overlap each other in physical space, but the GM has four options here:

1. Travelling to dimension B takes you to the same point on dimension B each time regardless of where you were when you left dimension B or where on earth you left from.
2. When you leave dimension B your location is set. So if you are in jail on dimension B when you leave, you return to jail on dimension B when you return, regardless of what happens on earth (and vice versa).
3. Your destination on dimension B is linked to your physical location on earth. (Think Zelda: Link to the past and the dark world- you're location is based 100% on where you were in Hyrule when you cross over, and vice versa).
4. You can go wherever, and this power becomes way cheaper than Teleport, and I highly discourage this option.

Both time travel and dimension travel lose some of the potential benefits of teleportation: you can't change your facing, your inertia (if you're falling) or anything else you would be able to do with teleport feats.

As time travel and dimension travel are instantaneous, without precognition or some kind of dimensional/temporal ESP, you could very easily end up travelling into solid matter. With dimensional movement you also have no guarantee of a hospitable environment you travel into.

That's just the tip of the iceberg. Let's examine the two real problems with these powers. How can they be abused to be UNBALANCED, and how can they be just TROUBLESOME.

• Unbalanced: Characters can travel to other dimensions or time periods to charge a weapon, heal up, repair things, or accomplish tasks, then return instantly to mid-fight, or potentially shoot across dimensions at foes here.
• Troublesome: The GM is forced to create other dimensions for the characters to go into, or deal with other eras of history that he may not have been prepared to run.
• Troublesome: The character can go back in time within his own timeline in an attempt to change things that are already campaign history, including main plot points.
• Troublesome: If the other PCs aren't brought along, one PC monopolizes the GM's time with their travel.
• Unbalanced: A PC who travels into other dimensions or the future may be expecting to return with alien/magic/future technology (though as GM you should just force him to spend power points on whatever he gets).
• Troublesome: The PC who interacts with other versions of himself or the party may require the GM to take over a past character, or allow the character to "role play with himself".
• Troublesome: PCs who want to dimension travel to alternate earths (like sliders) who want to use this to circumvent plots (like going to an alternate earth where this isn't happening).

While the powers seem broken, overall they are more troublesome than they are unbalanced. Both these powers can be abused during battle (and moreso if converted to attack powers). Here are some potential workarounds to the troublesome aspects.

• Establishing your dimensions ahead of time takes more work but limits where the PCs go. Perhaps they need to be aware of a dimension before they go to it with the power.
• You might limit PCs not to be able to time travel into a time period that they occupy. This could prevent them trying to use time travel as an "undo"button and prevent time travel into the immediate future or past. This can get further complicated if you need to track times that contain a time travelling PC and times that do not, and will prevent many time travelling complications (both troubling for the GM and plot related)
• A PC who time travels can find himself particularly at risk underground or in cities. How long as this cave been here, and when will it collapse? Don't guess wrong! Also jumping a few rounds into the futures gives enemies an opportunity to put a big stone block or other obstacle in your square for you to materialize into and get trapped in. (Maybe you can time travel back out, but it gets complicated for you to find an appropriate escape time that leaves you able to participate in the battle. 
• Timecop brought in the "don't touch yourself" rule that is carried in Shadows of Memories and in Project Almanac it gets even more severe with inability to interact with yourself at all without creating a self-destructive paradox. 
• Use alternate dimensions style of time travel discourages time travel to the past, as the future doesn't change "around" the other PCs- you just travel into another version of history, thus taking your character out of the campaign.
• D&D had introduced the concept of "Inevitables"- beings whose job it is to enforce certain laws, such as trying to keep the dimensions separated, or maintaining the proper timeline. A lot of abuse could draw attention from creatures like this, or in organizations like in Legends of Tomorrow or Star Trek Voyager who are tasked with dealing with troublesome time travelers and maintaining the timeline. 
• Flashpoint introduces the concept of "Time Boom" like a sonic boom caused by time travel, where the butterfly effect can have such intense effects that it would discourage messing with history less you screw things up for the worse. 
• If alternate dimensions are being abused in combat as escape routes, you could have complications arise in the alternate dimensions that a character needs to deal with alone (since he left his party behind). Likewise if he continues to hide in the past or future to heal up (or level up!).
• If a character doesn't have age immunity, you may want to punish him with rapid aging for all the time he spends in alternate time periods. Time could flow differently in different dimensions causing the PC to be ejected far in the future (or past) or something when he returns to his own dimension also. If each round in the alternate dimension is a day on earth, he can't stay long. Careful with this though, as the reverse is true, and if they find a dimension in which time does not flow, they could easily go there, do a bunch of healing/buffing/summoning etc, then return mid battle do wreak havoc. 
• Any power the PCs abuse is eligible to be abused by Villains, so it's not crazy to have villains do the same thing (or chase them into alternate dimensions) or be able to shoot across dimensions at them, or time travel themselves to mess with the party.

Remember, the powers should be USEFUL (they're spending points on them) and they can make for great adventure hooks, but they shouldn't be ABUSED. So going back in time to plant a tree for them to climb over a wall is one thing. Going back in time a day to amass an army who will show up right now is another thing altogether. Only nerf powers being abused, if the PC is using it in a plot friendly and less troublesome manner, this can be a good way of introducing plot to the characters.