Abyss Power

I'm trying to role play it out.

Travel through the Abyss is like a Hell Ride.

More refined/gradual Shadow movement is done through Shadow Tunneling which is more time and energy consuming.

I agree that some of the powers are over the top.

I just want to play it as having Logrus but with the added access to/through the Abyss.

Whereabouts is this Abyss power? I couldn't see it on a quick skim of Shadow Knight.

It comes at the end of the book where it describes a campaign where Brand comes out of the Abyss even more powerful than he was before.

The description is vague and basically describes having exalted powers.

It's NOT where Cody is at. He'd still have to learn Trump before being able to do the Trump stuff described.

The idea is: Instead of essayist the Logrus, Cody was 'Baptised' in the Abyss.

The Logrus draws power from the Abyss. Cody can do Logrus stuff but draw power directly from the Abyss instead of filtering it through the Logrus.

More homebrew than textbook.

Abyss travel is more hit/miss. A Run-away hell ride that only get to known Shadows or near unknown Shadows where he has to slow down and Shadow Tunnel to where he wants to go.

More refined travel is through more strenuous Shadow Tunneling.

More like broken Pattern travel.

The whole 'summoning Abyss creatures' is over the top. But yeeting someone into the Abyss is an option.

Then I've spent a lot of time and points barking up the wrong tree.

Well we can break it down a bit and see what we can learn.

Create Abyss Opening - If the player is out in Shadow they can rip open a hole to the Abyss. Things that fall through end up in the Abyss, but also the user can draw power through the Abyss opening.
-The second part sounds like the rules they use for Constructs where the owner(s) of a construct can use a focus
to draw power from the construct source and boost their other abilities. In this case the Abyss user has to open
rip open the portal to draw power from the Abyss. When the rip closes, or the user moves to far away from it they can't
draw power from it any more.
-The first part is straight forward, but potentially very powerful. Can the user rip open the portal beneath someone
causing them to fall into the Abyss? If so, since the Abyss is very deadly to those not "attuned to it" then they can
kill almost anyone in the game, unless the person has trumps to escape or shapeshift (and enough xp (15 pts)) to adapt
themselves.

Protect Contents from the Abyss - When in the Abyss you can prevent people and objects from being destroyed by the Abyss energies.
-Pretty straight forward.

Summon and Control Abyss Creatures - Like the name says, except it also say the creatures are harmless and basically non-sentient. An Abyss Master can mold them into Artifacts and other creatures powered by the Abyss.
-Part one is pretty useless unless you summon hundreds of them to block someone's path, forcing them to hack through all the blobs until they get free.
-Part two is interesting but it doesn't say how long it takes to make them or how powerful they can be. Conjuring has
rules for creating items, but this doesn't say you need conjuring to make them. The Abyss Master uses this instead of
conjuring maybe?

That is all the base 50 point power seems to give.

If the user also has Shapeshift they can:

Turn into fire form - Become untouchable, or burn whatever attempts to touch you. Pass through walls and objects. Do incredibly deadly damage to anyone you want by touching them.
-Super overpowered. Can't be hit or injured by any physical attacks, but can kill pretty much anyone they can touch.
They are in fire form, so I doubt eye-to-eye mental contact/domination could work against them because do they even
have eyes in that form? And can't make physical contact to try and dominate them either. Only limit might be that they
have to rip open a portal to the Abyss to draw the power from it, plus it doesn't say how much END it costs or how long
they can maintain that form.

Turn to Ice Form - become cold and solid. Resistant to most/all damage. No need to breath, etc...
-Not so bad, as I assume they can't move in that form, or are very, very slow (the description is they slow down all
their molecules to be so solid and cold). But again no idea the END drain or costs, etc.. but at least the benefits are
balanced by the drawbacks.

Advanced Abyss Powers (75 or 80 total cost. The rules can't even be bothered to give a set cost to it):

Corrupt/overwhelm trump - If the Advanced user also has Trump power they can override the trumps of anyone who is the Abyss.
-Wow. That's isn't going to come up often, unless the adventure/campaign take the players into the Abyss. But I guess
if the Abyss user can open a portal and drop people into the Abyss, then it becomes more useful. Drop their enemies in
to the Abyss, then override their trumps so no one can save them, and they can't trump out.

Time Manipulation - Abyss user can speed up and slow down time around them if they open a portal (or are already in the Abyss). Can be used as an attack.
-Another over powerful power/ability. Player controls time in their vicinity. Can't go back in time. But can freeze
everyone around them, then kill them off one by one. Can speed up time and age people thousands of years in moments,
basically killing all non-immortals instantly. Again, no idea hoe much Psych or END this requires or how easy it is
to do.

Inflict Abyss Powers - In the Abyss the Abyss Master can take possession of characters and switch all their attributes and powers around and change their personalities.
-Well I don't think I need to get into how insane this power is. Even if not used for "evil" and "winning the game"
it can be a game disruptor if the person uses it for good. Player X wants to change some of their stats and powers?
Remake their characters, well just go visit the Abyss Master in the Abyss and they can do all that for you.

How strong is the Abyss power vs the others?

Pattern is stronger unless in or next to the Abyss, and I guess also an Abyss portal? Which would technically be next to the Abyss, so Pattern would be weakened. But if no portal open then Pattern wins easily.

Logrus is completely dominated by the Abyss.

Trump is absolute defense against the Abyss powers.

And that is the breakdown.

So Abyss doesn't do all that much. Can't even travel through shadow (per RAW), but you can escape back to the Abyss from Anywhere in Shadow (I assume except close to Amber and the Pattern (or very near a broken pattern)) just by opening a portal and jumping through. Since Abyss is weak against Pattern until the portal is opened, probably means very hard or impossible to open a portal in Amber.

But the high cost is because what Abyss power can do dominates all the other powers in terms of shear damage/killing/destructive power, plus the ability to make unlimited Abyss powered artifacts, items and creatures. 

It's easiest to just consider it Logrus reskinned. The lack of hanging spells and tendrils is replaced with bringing other characters along for the ride. So no need to calculate points or anything else.