I once made an animated GIF (see left) following instructions from the internet,
and it was not terribly difficult, provided you used a drawing program that supported this function.
But you first have to create an image for each position in the game,
so that would take two orders of magnitude more work than creating a static image of a single position.
But for presenting chess games I think animated GIFs are a very poor tool.
They run through the game at a fixed speed,
which is too fast to notice anything of interest,
and annoyingly slow for the uninteresting part you have to go through to reach what you really want to see.
For Chess games I think it is very important to be able to control the stepping,
so you can view each position for the time it deserves.
Therefore I think it would be much better to use an Interactive Diagram configured as game viewer,
with its own 'button bar' of control buttons put somewhere on the page.
This is much easier to create too;
you just have to create the Diagram once, and add a parameter moveList=...
to it with all the moves of the game.
Such as shown at the end of this comment.
(Refresh browser cache first!)
But in the case of the Featured-Variant box I don't think this would be a good idea at all.
Showing a whole board would make the box too large,
(I think showing an entire 3-rank camp is already stretching it),
and showing part of the board of an animated game seems pointless.
Then it would not do more than having something flashing there.
And I guess most people would consider this annoying rather than attractive.
There is a fine line between being noticeable and being a distraction.
Text can only be understood if you first focus your attention on it, so that it can be read.
So those who would not systematically scan all elements of the page
(which includes scrutinizing all adds...) easily miss it, no matter how important the message might be.
Unlike an image, which you process intuitively whenever it is in your field of view,
in parallel with whatever else you were looking at,
and gives you a subconscious clue as to whether you would want to look at it.
Motion, however, draws your attention away from what you were really interested in all the time.
graphicsDir=/graphics.dir/alfaeriePNG35/
files=10
ranks=10
whitePrefix=w
blackPrefix=b
graphicsType=png
squareSize=35
darkShade=#E06666
lightShade=#FDE5CD
rimColor=#1C4587
coordColor=#FFFFFF
firstRank=1
promoChoice=QNRB
promoZone=3
symmetry=rotate
protected=9
counterStrike=9
enableAI=0
moveList=1. f5 g7 2. Wf4 h7 3. g5 f7 4. h5 b7 5. i4 Bb8 6. Wg4 O-O-O 7. Di3 We7 8. Bxb8 Dxb8 9. Wf4 Nc7 10. e4 i6 11. b4 g6 12. Dh4 Nj7 {A Knight on the edge is usually not a good idea!} 13. j4 gxh5 14. ixh5 ixh5 15. Dxh5 {A well-developed Dwarf is an asset, but you have to invest many moves.} Rji10 16. O-O-O Eh8 17. Nh4 f6 18. Rdg1 Di8 19. Bb3 Bxb3 20. Dxb3 Ej6 {Elfs on the edge are not so hot either.} 21. Qf3 Dh8 22. Nc4 Dg7 23. Ne3 Rch10 24. Rgi1 Rxi1 {By trading black gives up the control of the open file. Instead of 23... Rch10 it might have been better to play Ri3 in order to construct a battery with 24. Rci10} 25. Rxi1 h6 {A bad idea...} 26. g6 {... because the protected white passer is a lot stronger than black's isolated one!} Qh9 27. Ng4 {White leaves his Dwarf on b3, which is crucial for his King safety, hanging.} d6 28. Ni6 Gg9 29. Nxj8 Qxb3 {Black only notices the free gift now that he is forced to move the Queen.} 30. Ec2 Qxa3 31. Eb2 Qa4 32. Di6 {Dwarfs are great for forking, as most pieces are more valuable.} Gi9 {Pinning the Dwarf on the Rook only delays matters, as the pin is easily solved, and the Dwarf is sufficiently protected.} 33. Gh2 Exi6 {Rescuing the Elf would leave the Knight unprotected, so black rather sacrifices the Elf for the nasty Dwarf.} 34. Nxi6 Nb5 35. Wd5 {The Warlock cannot be traded away, because the Pawn protects it.} Wc7 {Black's Warlock was unprotected, though, and was now threatened by white's. It therefore had to seek protection.} 36. Wxd6xd5 {A Warlock can simply annihilate adjacent pieces, protected or not.} Gi7 37. Wc4 {A Good example of how dangerous a Warlock is in a dense melee of pieces. The adjacent Knight is now under annihilation threat by a hit-and-run or a rifle capture, but there also is a conventional attack on the unprotected Queen.} Nxc3 {Since the Knight can protect the Queen, black still has the opportunity to get a Pawn for the Knight.} 38. Wxc3xc4 {Again a rifle capture.} Qd7 39. Nxf6 {Black's scattered and poorly protected Pawn structure is fair game. 38... Qc6 to protect the Pawn and attack the Warlock might have been better. Black doesn't seem willing to expose his Queen to the Warlock, though. But in this situation the Warlock is probably still stronger.} Dxf6 40. Exf6 Kb9 {Black must evade the accidental check from the Elf.} 41. Wc5 {Again the Warlock's protection makes it immune to trading.} Qd9 {Again escaping the Warlock for no good reason.} 42. Ng7 {A discovered attack on the Goblin.} Qg9 {Black ignores it...} 43. Rxi7 {... and as a consequence loses another exchange. He is no so far behind in material that the outcome seems sealed. } Qxi7 44. Qi3 Ni5 {Throwing away another Knight doesn't make things better. Even if it was a rather inactive one.} 45. Nh5 {White gets over-confident, and instead of immediately taking the Knight, interjects an attack on the black Queen.} Qg9 {The Queen can attack white's Warlock in the evasion, though.} 46. jxi5 {White decides to take Warlock + Knight for Queen.} Qxc5 47. bxc5 Wxc5 48. Gc2 {White has to defend against the mate threat 48... Wb3#. A Goblin, Elf or even a Dwarf is sufficient protection against a mate from an unsupported Warlock.} Wa3 49. Kd1 Ri10 50. Qj4 a6 51. Qj9 {Leaving unprotected pieces on a sparsely populated board while your King is not shielded is always a very bad idea when the opponent has a Queen!} Ka8 52. Qxi10 {That finishes Black. Apart from the Warlock, which he has parked away from the action for making a pointless spite check, he only has a Dwarf to defend his King, against a Queen and two sliders stronger than Rook.} a5 53. Qa10 Da9 54. Gxc8 Ka7 55. Ed4 b6 56. Qxa9 {checkmate!}
pawn::::a3-j3
dwarf::K:duke:a2,j2
knight:N:::b2,i2
bishop::::c2,h2
rook::::a1,j1
elf::BW:promotedbishop:d2
goblin::RF:promotedrook:g2
queen::::f2
warlock::KNADmabKcaKcabK:lion:e2
king::::f1
I once made an animated GIF (see left) following instructions from the internet, and it was not terribly difficult, provided you used a drawing program that supported this function. But you first have to create an image for each position in the game, so that would take two orders of magnitude more work than creating a static image of a single position.
But for presenting chess games I think animated GIFs are a very poor tool. They run through the game at a fixed speed, which is too fast to notice anything of interest, and annoyingly slow for the uninteresting part you have to go through to reach what you really want to see. For Chess games I think it is very important to be able to control the stepping, so you can view each position for the time it deserves.
Therefore I think it would be much better to use an Interactive Diagram configured as game viewer, with its own 'button bar' of control buttons put somewhere on the page. This is much easier to create too; you just have to create the Diagram once, and add a parameter moveList=... to it with all the moves of the game. Such as shown at the end of this comment. (Refresh browser cache first!)
But in the case of the Featured-Variant box I don't think this would be a good idea at all. Showing a whole board would make the box too large, (I think showing an entire 3-rank camp is already stretching it), and showing part of the board of an animated game seems pointless. Then it would not do more than having something flashing there. And I guess most people would consider this annoying rather than attractive. There is a fine line between being noticeable and being a distraction. Text can only be understood if you first focus your attention on it, so that it can be read. So those who would not systematically scan all elements of the page (which includes scrutinizing all adds...) easily miss it, no matter how important the message might be. Unlike an image, which you process intuitively whenever it is in your field of view, in parallel with whatever else you were looking at, and gives you a subconscious clue as to whether you would want to look at it. Motion, however, draws your attention away from what you were really interested in all the time.
comments
Sample game
1. f5 g7 2. Wf4 h7 3. g5 f7 4. h5 b7 5. i4 Bb8 6. Wg4 O-O-O 7. Di3 We7 8. Bxb8 Dxb8 9. Wf4 Nc7 10. e4 i6 11. b4 g6 12. Dh4 Nj7 13. j4 gxh5 14. ixh5 ixh5 15. Dxh5 Rji10 16. O-O-O Eh8 17. Nh4 f6 18. Rdg1 Di8 19. Bb3 Bxb3 20. Dxb3 Ej6 21. Qf3 Dh8 22. Nc4 Dg7 23. Ne3 Rch10 24. Rgi1 Rxi1 25. Rxi1 h6 26. g6 Qh9 27. Ng4 d6 28. Ni6 Gg9 29. Nxj8 Qxb3 30. Ec2 Qxa3 31. Eb2 Qa4 32. Di6 Gi9 33. Gh2 Exi6 34. Nxi6 Nb5 35. Wd5 Wc7 36. Wxd6xd5 Gi7 37. Wc4 Nxc3 38. Wxc3xc4 Qd7 39. Nxf6 Dxf6 40. Exf6 Kb9 41. Wc5 Qd9 42. Ng7 Qg9 43. Rxi7 Qxi7 44. Qi3 Ni5 45. Nh5 Qg9 46. jxi5 Qxc5 47. bxc5 Wxc5 48. Gc2 Wa3 49. Kd1 Ri10 50. Qj4 a6 51. Qj9 Ka8 52. Qxi10 a5 53. Qa10 Da9 54. Gxc8 Ka7 55. Ed4 b6 56. Qxa9#