What each of them do
bow : faster shoot and +dmgmultiplier (based on speed of the arrow x multiplier)
elytra : +dmg and firework speed
clay : +dmg, makes clay blocks
minecart : +basedmg, alot of variants
spear : +dmgmultiplier (speed of spear + speed of opponent x dmgmultiplier)
sword : +dmg
slime : splits, +dmg
magma : splits, makes fire, and +dmg