What words and phrases indicate that Polyphemus (the Cyclops) will be a formidable opponent for Odysseus?
Here are some quotes to help you out:
There are words of foreboding as part of Odysseus' narration: "A sudden foreboding told my fighting spirit I'd soon come up against some giant clad in power like armor-plate--a savage deaf to justice, blind to law" (218) and "But he proved no lovely sight to my companions" (218). As readers, when we read these words, we sense that Polyphemus is going to be a formidable foe.
There are words describing Polyphemus and his actions: "He flung them down in the cave--a jolting crash" (219). The words jolting and crash show us that Polyphemus is more powerful than any human. "Then to close his door he hoisted overhead a tremendous, massive slab--no twenty two wagons, rugged and four-wheeled, could budge that boulder off the ground, I tell you, such an immense stone the monster wedged to block his cave" (219). The description suggests how hard it would be to move the slab of stone, yet that it was easy for Polyphemus to move shows us how strong and powerful a creature he is.
There are words that Polyphemus says: "Out on a trading spree or roving the waves like pirates, sea-wolves raiding at will, who risk their lives to plunder other men?" (219) Polyphemus already suspects Odysseus and his men to be raiders or pirates and doesn't seem to think too highly of them. "You must be a fool, stranger, or come from nowhere, telling me to fear the gods or avoid their wrath! We cyclops never blink at Zeus and Zeus' shield of storm and thunder, or any other blessed god--we've got more force by far. I'd never spare you in fear of Zeus's hatred. You or your comrades here, unless I had the urge." (220). Most Greeks were god-fearing people. The fact that Polyphemus outright states that he does not fear the gods and isn't struck down immediately shows Odysseus and his men that the gods are not going to help or intervene.