[porkynator]

1.
DNF

Spoiler (Click to View)

DNF, feat. the worst DR in 9 ever:
(D' F' U)
(L D2 L2 B2 L' F)
optimal HTR from here is 10 moves, even with NISS.

2.
Scramble: R' U' F R L' B2 U2 L2 U F D R2 F D' B L2 F' U2 F R2 B2 R' U' F
Solution: U' D2 B D' R F' U2 L' U2 B F2 D2 F' R2 U2 F' L2 F U2 D2 R2 (21)

Spoiler (Click to View)

Backup 23:
U D2 B D //EO (4/4)
B2 L' B2 R F //DR (5/9)
U2 F2 [slice1] L [edges] D2 //Some blocks (4/13)
R B2 L D2 [slice2] R L2 //3e (6/19)

[edges] = R2 B F' U2 B' F (6-0/25)
[slice1] = [slice2] = M2 (-2/23)


Final solution, from a different DR:
U' D2 B D' //EO (4/4)
R F' U2 L' //DR (4/8)
U2 F B R2 * B D2 R2 //2e2c (7/15)

* = R2 F D2 F' R2 U2 F' L2 F U2 B' (11-5/21)

Optimal DR finish

3.
Scramble: R' U' F L' B U2 L2 U F2 L2 F2 D' R2 B2 R D' R2 U2 R B U' B R' U' F
Solution: U B2 R' B' L' U' L2 B2 L2 F2 D' F2 L2 D2 L2 B2 L2 B2 R U F2 D' U' B2 (24)

Spoiler (Click to View)

U B2 R' B' //EO (4/4)
L' (B2 U D F2 U' R) //DR (7/11)
U' L2 * U //Corner HTR (3/14)
B2 D2 [R2 F2 L2 F2 L2] //3e (7/21)

* = B2 L2 F2 D' F2 L2 B2 U' (8-4/25)

Replace [] with L2 B2 L2 B2 R2 to cancel one move with inverse.

I am happy with the result, but a bit disappointed that I have spent the whole hour trying out EOs on one axis and just on normal scramble.
Without NISS there were 8 of them:

U D L B - nothing good from here
U B2 R' B' - my final solution from here
L' R' U' B - I had like a DR in 14 from D2 R...
L' B2 D B - R simplifies for DR, but nothing good after that
B R' U B - I found this DR: D' L2 F2 R' D' R2 D, not very good
B U R' B' - I found this DR: L U F2 D2 R' U2 R, seems ok
B' L' D B - nothing good from here
B' D L' B - 3 nice pairs!

I spent about half an hour on the last EO, there was a lot to try:
1. B2 D (actually finish EO with B') then maybe R D B2 D' ?
2. L' D' L then I don't know B2 R2 D?
3. (D L U') this looks promising, possible continuation L2 U L' B2
4. (L U L) and then continue with DR with good corners on inverse?

DNF, 21, 24 = DNF