Grudgestomp's rider narrowly ducks the Eldritch Blast that fires wide. He thinks it is prudent to fire back.
Rolls
Grudgestomp's attack against the winch - (1d20+6)
(16) + 6 = 22
Bludgeoning damage - (2d8+4)
(73) + 4 = 14
Goblin's shortbow attack against Finn - (1d20+4)
(9) + 4 = 13
Piercing damage - (1d6+2)
(4) + 2 = 6