Magic

[cinelli]

-----------------------------
|1     |2     |3     |4     |
|      |      |      |      |
|      |      |      |      |
-----------------------------
|2     |      |      |      |
|      |      |      |      |
|      |      |      |      |
-----------------------------
|3     |      |      |      |
|      |      |      |      |
|      |      |      |      |
-----------------------------
|4     |      |      |      |
|      |      |      |      |
|      |      |      |      |
-----------------------------

Across
1. --- sceptred isle
2. Competitive trial of speed
3. The bard's river
4. House on a roof
Down
1. Snare
2. Possess
3. Religious image
4. Dispatched

But that is only the beginning. Using the clue
"Twitters merrily" = (10,9,16,8,11,7)
transfer six letters to another 4x4 grid and complete that grid so that it is a magic square. In a magic square, all rows, columns, diagonals and certain other cells add to 34.

Cinelli

[Howyoudoin]

-----------------------------
|1   
Across
1. --- sceptred isle
2. Competitive trial of speed
3. The bard's river
4. House on a roof
Down
1. Snare
2. Possess
3. Religious image
4. Dispatched

But that is only the beginning. Using the clue
"Twitters merrily" = (10,9,16,8,11,7)
transfer six letters to another 4x4 grid and complete that grid so that it is a magic square.  In a magic square, all rows, columns, diagonals and certain other cells add to 34.

Cinelli

I thought I was being so clever completing the first part of the puzzle.

I don't even understand what the second part means.

HYD

[GoSeigen]

-----------------------------
|1     |2     |3     |4     |
|      |      |      |      |
|      |      |      |      |
-----------------------------
|2     |      |      |      |
|      |      |      |      |
|      |      |      |      |
-----------------------------
|3     |      |      |      |
|      |      |      |      |
|      |      |      |      |
-----------------------------
|4     |      |      |      |
|      |      |      |      |
|      |      |      |      |
-----------------------------

Across
1. --- sceptred isle
2. Competitive trial of speed
3. The bard's river
4. House on a roof
Down
1. Snare
2. Possess
3. Religious image
4. Dispatched

But that is only the beginning. Using the clue
"Twitters merrily" = (10,9,16,8,11,7)
transfer six letters to another 4x4 grid and complete that grid so that it is a magic square. In a magic square, all rows, columns, diagonals and certain other cells add to 34.

Cinelli

Spoiler:

| 2| 9|16| 7|
| 8|15|10| 1|
|13| 6| 3|12|
|11| 4| 5|14|

Found by guessing the answer to the clue is "chirps" and transferring as follows before completing the magic square:

|  | 9|16| 7|
| 8|  |10|  |
|  |  |  |  |
|11|  |  |  |

GS

[cinelli]

Well solved, GoSeigen. Making sense of the slightly vague instructions was part of the challenge.

Cinelli