Tails is fixing something his weapons in Sonic Battle (for GBA) but while he's fixing his Arm Cannon thing, that punching glove that comes from the ground socked him good, even knocked a tooth out, he went up so fast that his screwdriver and socks havent even had a chance to drop.

If you're wondering if Tails' face is swollen, it is, the bigger eye part is supposed to represent a black eye, and yes that's his tooth in his hand.