Legendary Creature - Human Samurai 3/2, 2RR (4) Fumiko the Lowblood has bushido X, where X is the number of attacking creatures. (When this blocks or becomes blocked, it gets +X/+X until end of turn.) Creatures your opponents control attack each turn if able.1
Illus. Michael Sutfin
2/1/2005: X is variable. The bushido bonus is calculated each time Fumiko's bushido trigger resolves, based on the number of attackers at that time.
2/1/2005: Fumiko's ability doesn't force an opponent to pay for effects in order to be able to attack with his or her creatures (such as Ghostly Prison, for example).
2/1/2005: Fumiko's ability doesn't force tapped creatures or creatures with summoning sickness to attack.
8/1/2008: A creature required to attack or block if able in a given turn only has to do so during the first combat phase that turn in which it's able. Basically, each combat phase in that turn, you ask "did this creature attack/block this turn?" and "can this creature attack/block this phase?" If the answers are "no" and "yes" respectively, then it must attack or block as required. This is important if a turn somehow gains extra combat phases.
Betrayers of Kamigawa
(Rare)