A scene from Saturday, before the Oogma encounter:
The river races faster and faster, disappearing over an edge where it plummets to unknown depths. Four adventurers are in the water, struggling just to stay afloat as the current pulls them inexorably toward the falls. Just above the falls, though, a rope bridge extends all the way across, just barely reachable from the water. Ratfolk archers line the banks on either side, preventing the heroes from reaching the banks. Unknown to the adventurers, the Ratfolk have a huge net extended just beyond the edge of the falls to catch anyone who goes over. Their intent is to sacrifice captives to appease Oogma.
Elerisa the elven princess lunges for the bridge and catches hold. Wren the elven druid reaches for it too, and she grabs it. Then it's Fiona the halfling druid's turn. Her player announces she is too short to grab the bridge. I am about to let her lunge for it just like the others, but since she doesn't seem alarmed, I allow her statement to stand.
"I reach for Wren's waist so I can hold on to her," she says. She rolls well and succeeds.
Then it's Pinky the dog's turn. Pinky is being played by a girl down the street who doesn't normally join us. She decides to latch on with her teeth to Fiona's leggings, and she succeeds. We end up with two elves holding on for dear life to the bottom of a rope bridge as the river tries to pull them over the edge of the waterfall, while a halfling and her dog form a chain clinging to the weaker of the two elves.
Elerisa climbs up onto the rope bridge, then starts firing arrows into the Ratfolk. They respond with a volley of arrows that knocks her unconscious. She falls from the bridge and into the water, where she is caught by the net as she goes over the falls.
Wren attempts to pull herself up onto the bridge, but the weight of Fiona and Pinky, plus the powerful pull of the river, is too much. She can't hold on much longer, and Fiona and Pinky are getting pounded by the current. The Ratfolk prepare to fire at Wren to force her to let go.
Fiona: "Can Pinky hold onto Wren's leg instead of mine?"
Fiona: "Pinky, hold on to Wren's leg. I'll help you."
Pinky: "I switch to Wren's leg."
GM (handwaving the roll): "Ok, Pinky, you're holding on to Wren's leg now."
Fiona: "Can I hold on to Wren with my legs instead of my hands?"
GM: "Sure, but you'll be upside down with your head in the water."
Fiona: "Ok. I do that. What do I roll?"
GM: "Roll a d20." (scrambles to decide what the target DC should be, and what kind of skill check it should be)
Fiona (rolls): "19?"
GM (relieved because it's a very high roll so I don't need to decide after all): "Yep, you succeed."
Fiona: "With my free hands I cast Entangle on the Ratfolk."
GM (chuckling at the revelation of where this plan is going): "The river makes it difficult to concentrate. Roll a concentration check, and beat a 20."
Fiona beats a 20.
And so it was that the halfling druid, while effectively being waterboarded, successfully cast a spell that entangled several of the Ratfolk.