FIVE PIECE RIGHT HANDICAP (white removes rook, bishop, both lances, and his right knight) is a significantly smaller handicap than five piece left.
Both of black's major pieces are pointed at white's left, so he needs his knight there much more than his right knight. Black can reposition his major pieces to attack white's right, but this takes an extra tempo or two. This gives white enough time to make a rather tough defense using three generals on the right. The classic book "Shogi Taikan" by Kimura, 13th lifetime Meijin, shows the direct attack utilizing a climbing silver as leading to an easy win for black, but a later book by the late Itaya 8 Dan shows a better defense for white. A better version of the attack is given by Kiriyama Kiyosumi 9 Dan, as follows:
The line runs : 1... G7b 2 P7f P8d 3 B6f G8c 4 P8f (planning to attack the target on 8d) P6d 5 P5f (to give the bishop a retreat in case of ... P6e) S8b 6 R8h G5b (shifting his army towards the side under attack) 7 P8e Px8e 8 Rx8e P*8d
After 8... P*8d
9 R8h (not 9 Bx8d? Gx8d 10 Rx8d B*9e forking king and rook) G6c 10 N7g (now 11 Bx8d is a threat; the rook's promotion at the modest price of bishop for gold and pawn would be deadly here, with the white king still at home) G67d 11 S7h (now one more piece is needed for the attack to succeed) K5b (the white king is both safer and more useful here) 12 K4h (The advance of the center pawn and the possibility of bishop checks after a later sacrifice make it unwise to leave the king at home) P5d 13 K3h S4b 14 S8g
S5c (14... P9d 15 P7e P6e 16 B4h G6d 17 S7f S9c 18 P9f S5c 19 P9e Px9e 20 P*9b S8b 21 Nx6e S4d 22 P*8e Px8e 23 Sx8e Sx6e 24 P*8d G9c 25 Lx9e is overwhelming) 15 P7e (Kimura gave S9f in a similar position, but the defense ... P9d and ... S9c as given by Itaya is not so simple to refute) P6e 16 B4h G6d 17 S7f P9d 18 P*8e S9c 19 Px8d Sx8d 20 P*8e S9c 21 P7d! (activating the bishop) G6x7d 22 Sx6e Gx6e 23 Nx6e S6d 24 P8d G7d 25 P8c+ S6e 26 Bx9c+ (black is clearly winning) P*8f 27 +B7a K4b 28 G*2b! (surrounding the king) P3d 29 Gx2c.
With both a huge material advantage and the enemy king trapped, black should win in a few more moves.
A quieter alternative for black, suggested by Naito Kunio 9 Dan for six piece handicap but even more appropriate here, is to build a "missile silo" by an early P4f and S3h-4g to protect the head of the bishop on 5g. Since this is a slow plan, I think black should first prevent the three general defense by an early P9f-9e, build the missile silo, castle, and then double on the edge (lance in front). Next he can break through by attacking the 9c pawn three times (lance, rook, and bishop or knight) while it can only be defended twice. For example, after 1... G7b 2 P7f P8d 3 P9f G8c 4 P9e G5b 5 P5f P6d 6 B6f G6c 7 P4f (starting to build the silo to house the "missile", meaning the bishop, on 5g) G67d 8 N7g (stops ... G6e) K5b 9 S3h P5d 10 S4g P6e 11 B5g (completing the "silo") G6d 12 L9g S8b 13 R9h P7d (note that because black has guarded his bishop's "head" with his silver, an attack by 13... P5e 14 Px5e Gx5e can be met simply by 15 P*5f, driving back the gold) 14 P8f K6c 15 S7h S4b 16 S8g (This is to guard the head of the knight; otherwise once white gets a pawn in hand he could play ... P7e and answer Px7e by P*7f) P3d 17 K4h (not strictly necessary, but since black has already chosen a slow plan he might as well improve his position before attacking) P4d 18 K3h S4c 19 G65h P3e 20 P1f (a useful escape hole for the king) S3d 21 P8e (starting the attack, now that black's position is secure)
P7e (if 21... Px8e 22 P9d Px9d 23 Lx9d P*9c 24 Lx9c+ Sx9c 25 Bx9c+ Gx9c 26 Rx9c+ and although the material exchange was fairly even black has promoted his rook with an overwhelming attack) 22 Px7e Px8e (else 23 S7f) 23 Nx8e P*8d 24 Nx9c+ Sx9c 25 P9d S8b 26 P9c+
winning material and breaking in.
If white avoids 2... P8d for fear of the above quick attack, black can prevent it altogether before attacking the edge : 1... G7b 2 P7f S8b 3 B6f G5b (If white omits this black can play a quick P9f-9e-9d as in six piece handicap) 4 P8f (4P9f P6d 5 P5f G56c 6 P9e G7d 7 N7g is also good but a bit difficult) P6d 5 P5f G56c 6 P8e G7d 7 N7g (stops ... G6e or ... Gx8e) K5b (at high handicaps the white king is usually best placed near the center, but off the back rank) 8 P9f (Here too a good alternative is the "missile silo" by P4f, S3h-4g, and B5g, then S7h-8g to guard the knight's head, followed by P9f-9e, L9g, R9h, and castling) P5d 9 P9e P6e 10 B5g G6d 11 P9d (White is threatening to stir up trouble by ... P5e so there's no time to castle here) Px9d 12 Lx9d P*9g! (Keeps the rook from promoting on the 9th file) 13 L-9b+ (13 P*9c is also strong)
P7d (or 13... P5e 14 Px5e Gx5e 15 B7e S4b 16 R5h P*5f 17 B6d G4e 18 P4f winning the key center pawn) 14 +Lx8b Gx8b 15 R8h P7e 16 Px7e G7c 17 R8f P5e 18 Px5e S4b 19 B3e Gx7e 20 R9f
and the rook promotes (analysis by Kiyono 8 Dan).
Lessons from this handicap :