Graphics
Twice Risen uses a lot of DooM's original textures, but it also
has lot's of new textures and textures that are based on DooM's
textures. There are some graphics that I've seen in other megawads,
and used myself too...
Also the god-mode graphics has been changed from black/white to bluescale!
Weapons
New weapons are very cool...
Pistol is replaced with some kind of strange little gun that shoots green long missiles. I think that they give the damage of one plasma bullet. Chaingun is changed into rapid firing version of this.
Shotgun is replaced by a cool machine gun that really teaches a lesson to the monsters (grin).
Super Shotgun is replaced by a shotgun-like quite fast weapon.
I never found the rocket launcher, or what ever it is now, but I bet it's cool too...
Plasma rifle and BFG9000 still have the old graphics, but they are new weapons. I bet they have new graphics in final release. They both use mines... Another one shoots mines that blow up after a while, and another places mines on the ground. However the ground mines don't seem to blow up alway, and that's why I never used that weapon...
Monsters
I was a bit dissapointed... I thought that there would be an army of new
monsters, but I found out that there was only one new monster... A marine
like you who shoots you with your basic ammo. I hope there will be more
new monsters in final release.
Levels
The levels were very well detailed and technical. Some of the levels
actually bring somehow Eternal DooM to my mind, although they are
very different... Good thing is that I didn't even once think that
"hey, this place needs more detail". Bad thing about the levels was
that they were far too easy. I wonder how can the authors claim that
skill level 3 is like "Ultra Violence" in DooM 2?!? I played it on
skill 4 without any big problems!!! I hope they give a real challenge
to us DooM Masters too in the final release!
Final comments
Twice Risen is a very good Total Conversion which is very enjoyable
to play. It never gets boring, but it could be a bit harder. The
levels are very good looking, which always adds a lot in the feeling.
Here's how valuable it is
The look: Very good. Good details.
The feel: Again, very good. Gives you a killer feeling.
Hardness: Too easy for a DooM Master.
Mindwork: Not really needed.
Points: 
Download: TRISEN01.ZIP (1 Mb)
Homepage: www.doomworld.com/twicerisen/tr.shtml
All levels have very good looking structures.
Colored lightning. Always cool.
Ready to leave with your space ship?
This should do it...
The only new enemy that I found.
Another cool new weapon.
Mastermind was surpisingly easy with this plasma rifle-like gun.
God mode has been changed to look really cool!