In this card's artwork, "Kizan" appears to be recharging his armor's power and regretting what he has done to Shien, explaining the name and effect of the card.
This card's artwork is similar to that of "Shien's Scheme".
This card appears in the artwork of "Damaging Hand".
The "one day of peace" in question most likely corresponds to one full "cycle" of each players' turns. Some strategy games, namely turn-based ones, divide each full cycle of all players' turns into "Days"; a notable example of such games that do this are the Japanese Wars games.