This next merge episode had a near unanimous vote. A lot of these can fit the bill but this is:
PALAU!
This merge episode had possibly the most unique set-up in the show's history. Now technically, the show didn't call this a merge but for the purposes of this list, I'm going to treat this episode as such. We come off Ulong being down to 2 tribe members losing their last immunity challenge to set up a tiebreaker challenge for survival. Steph won this and went back to tribe camp alone.
I thought the beginning of this episode was very interesting. We never saw any castaway be at camp completely by themselves and we got to feel the emotions Steph was which was that it's a scary experience being in the middle of an island by yourself. Thankfully, Steph's suffering was shortlived as she was told to move to Koror's camp. Now we were also finally going to see Koror have tribal lines. They lived with each other for a few weeks being undefeated and only sacrificing Willard in a double tribal. On paper, this should be a good episode, especially with Steph having a prior connection with Tom in the beginning of the game. Unfortunately, it just wasn't well executed. Koror became set on voting out Steph as soon as she got there. The only reason that didn't happen the first episode was because Coby went awall. He told Steph all the tribe's secrets and just went off on them. This alienated him from the rest of the tribe and pissed off Koror so much that they decided to vote him out before Steph. In the end, he was disposed of quickly with 7 votes.
Another reason why this episode is low is because there wasn't much impact from it. Coby was kind of always on the bottom of the tribe and this only carried Steph a few more episodes. The only person Coby really had an alliance with was Greg and I feel like those 3 would've been picked off anyway. So in the end, this episode just got Steph out of Ulong camp with the rest being a filler to set up the end game battle between Tom and Ian.
Stay tuned for #24! Hint- this merge turned allies on the bottom against each other
29. Thailand
28. Guatemala
27. China
26. Exile Island
25. Palau
Borneo
Australian Outback
Africa
Marquesas
Amazon
Pearl Islands
All Stars
Vanuatu
Cook Islands
Fiji
Micronesia
Gabon
Tocantins
Samoa
Heroes vs. Villains
Nicaragua
Redemption Island
South Pacific
One World
Philippines
Caramoan
Blood vs. Water
Cagayan
San Juan Del Sur
IMO, this write-up is way too focused on the "strategy" behind the episode. This ranking isn't "Survivor Merge Vote-Offs". I remember this episode for, like what you said, Coby going "awall". I found his antics very entertaining and they were featured throughout the episode, like him telling Stephenie all their plans and arguing with Tom about the Palauan fisherman. Also, if you're looking for humour, didn't casuals find the "good-old fireman" Tom getting really drunk funny? Lastly, seeing Stephenie return to camp on her own and seeing how Koror interacted with her entertained me. Honesty, I don't even like Palau, but I think its merge episode was decent. Having said that, most merge episodes are amazing, so I'm not really complaining about where the episode was placed, I was more concerned about the write-up focusing solely on "strategy", which makes me worried about amazing merge episodes like Nicaragua that were amazing for reasons other than "strategy".