Hearts 1♠

1♣ - 1♠ shows 5+♥ and a shorter spade suit. Opener relays with 1NT.

1♣ - 1♠ -
1NT!	(R)

1♣ - 1♠ - 1NT -
2♣!	13+, 5+♥, no (5=♥, 5+♦♣)
2♦!	8–12, 5=♥, 4+♦♣
2♥!	8–12, 5+♥, 4=♠ or (5332)
2♠!	8–12, 6+♥, no side suit
2NT!	8–12, 6+♥, 4=♦♣
3♣!	13+, 5=♥, 5+♦
3♦!	13+, 5=♥, 5+♣
3♥!	8–12, 6+♥, 5=♣
3♠!	8–12, 6+♥, 5=♦
3NT!	8–12, 6+♥, 5=♠
4♣♦	8–12, 6+♥, 6=#

Viking has 3♦ at 8–12. I adjusted it here to 13+ because 2♦ already handles 8–12 well.

Strong 2♣

Opener relays with 2♦ and responder gives the 8–12 answers, except for 5♥ with a minor.

1♣ - 1♠ - 1NT - 2♣ -
2♦!	(R)
2♦ - 2♥!	5+♥, 4=♠ or (5332)
2♦ - 2♠!	6+♥, no side suit
2♦ - 2NT!	6+♥, 4=♦♣
2♦ - 3♣♦	5=♥, 4=#
2♦ - 3♥!	6+♥, 5=♣
2♦ - 3♠!	6+♥, 5=♦
2♦ - 3NT!	6+♥, 5=♠
2♦ - 4♣♦	6+♥, 6=#

Minor 2♦

1♣ - 1♠ - 1NT - 2♦ -
2♥!	(R)
2♥ - 2♠!	4=♣
2♥ - 2NT!	4=♦
2♥ - 3♣!	5=♣
2♥ - 3♦!	5=♦
2♥ - 3♥!	6=♣
2♥ - 3♠!	6=♦

Spades or balanced 2♥

The same relay serves 8–12 and 13+, which bid 2♥ at the same level.

1♣ - 1♠ - 1NT - 2♥ -
2♠!	(R)
2♠ - 2NT!	(5332)
2♠ - 3♣!	4=♠, 6+♥
2♠ - 3♥!	4522
2♠ - 3♠!	4513
2♠ - 3NT	4531
2♠ - 4♣!	4504
2♠ - 4♦!	4540

One-suited 2♠

The same relay serves 8–12 and 13+, which bid 2♠ at the same level.

1♣ - 1♠ - 1NT - 2♠ -
2NT!	(R)
2NT - 3♣!	(6322)
2NT - 3♦!	(6331)
2NT - 3♥!	(7321)
2NT - 3♠!	3730
2NT - 3NT	2722
2NT - 4♣!	3703
2NT - 4♦!	0733

Two-suited 2NT

2NT shows 6+♥ with a 4-card minor. Opener relays with 3♣ to ask which.

1♣ - 1♠ - 1NT - 2NT -
3♣!	(R)
3♣ - 3♦!	4=♣
3♣ - 3♥!	4=♦