Chess in Rabbinic sources

I saw the following interesting roundup in Birkas Yitzchak on parashat Tazria:

"Ibn Ezra wrote the following poetic riddle about the game of Chess. {J: ishkaki / shach-mat = Check Mate. At least, it is attributed to him.}

A land without earth,
Her kings and officers,
Go about without souls.
If the king is destroyed,
Not a soul shall live.

Rashi zal called chess 'ishkis', from the Old French word. {J: Modern French: les échecs.}

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This game is mentioned in the gemara {Ketubot 61b} and is called by the name ורדשיר.

{J: That gemara reads:

רשב"ג אומר וכו':

היינו תנא קמא איכא בינייהו דמיטללא בגורייתא קיטנייתא ונדרשיר:

To give the background, the Mishna had stated:

R. ELIEZER SAID: EVEN IF SHE BROUGHT HIM²²  A HUNDRED BONDWOMEN HE MAY²³  COMPEL HER TO WORK IN WOOL; FOR IDLENESS LEADS TO UNCHASTITY. R. SIMEON B. GAMALIEL SAID: EVEN²⁴  IF A MAN FORBADE HIS WIFE UNDER A VOW TO DO ANY WORK HE MUST DIVORCE HER AND GIVE HER KETHUBAH²⁵  TO HER FOR IDLENESS LEADS TO IDIOCY.²⁶

And in the gemara, the following distinction was made between R' Eliezer and R' Shimon ben Gamliel:

 R. SIMEON B. GAMALIEL SAID etc. Is not this the same view as that of the first Tanna?²⁸  — The practical difference between them [is the case of a woman] who plays with little cubs²⁹  or [is addicted to] checkers.³⁰

Soncino defines it as "checkers", and gives the following footnote:

nardeshir, the name of a game played on a board; 'chess' (Rashi). [So named after its inventor Ardeshir Babekan, v. Krauss T.A. III, p. 113]. A woman who spends her time in this manner may be exposed to the temptation of unchastity but is in no danger of falling into idiocy.

}

Rabbi Yehuda HaLevi, in his sefer HaKuzari, called this game by the name אשקאקש -- in Kuzari, essay 2, siman 20, 6th introduction.
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In my sefer She'elot uTeshuvot, there is the following question: If it is permitted for a man to play chess if he took a vow not to play at all. And the Rav from Anchora {?} answered that this game is not a melacha {work} but rather a chochma {craft} and thus, the vow does not take hold upon it.
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There are poskim who permit playing chess on Shabbos, since this is oneg Shabbos. (Pachad Yitzchak)
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The author of Shiltei Giborim (upon the Rif) writes at the end of the masechta of Eruvim: that the game of chess requires great wisdom. Therefore it is permitted to play it on Shabbos. But not to play it during the time of Torah and davening, for this is forbidden as well during the week.