Flowerfoot Swordmaster

In the rare case where the creature doesn't have the offspring ability when it enters, the ability won't trigger even if you paid the offspring cost.

The token copies exactly what was printed on the original creature and nothing else, except it's a 1/1 (unless that creature is copying something else; see below). It doesn't copy whether that creature is tapped or untapped, whether it has any counters on it or Auras and Equipment attached to it, or any non-copy effects that have changed its types, color, or so on.

Many creatures with offspring abilities have other abilities that refer to them as "this creature" rather than referring to them by name. This difference is for clarity purposes and does not change the function of any of these abilities.

If a spell or ability you control has one or more of its targets changed to a creature you control with a valiant ability, that ability will trigger if that creature hasn't yet been the target of a spell or ability you control this turn.

Flowerfoot Swordmaster's last ability affects only Mice you control at the time it resolves, including Flowerfoot Swordmaster itself (as long as it's still a Mouse at that time.) Mice you begin to control later in the turn or creatures that become Mice later in the turn won't be affected.

You can pay an offspring cost only once as you cast a spell with offspring. You can't try to pay it multiple times to get more token copies.