Armor-Piercing Attack: Cranky's pogo cane is able to harm Snowmads with helmets, which would otherwise protect them or even hurt Kongs who jump on them.
2½D: Tropical Freeze expands on what Returns did by adding curving paths and Camera Perspective Switch during segments like barrel cannon sequences. Certain Minecart Madness levels also involve jumping back and forth between parallel rails.
A Load of Bull: One of the new enemies is Buffaloafer, a Cape buffalo.
Abnormal Ammo: One of the enemies is a penguin archer who fires fish as projectiles. Diddy can still use his Peanut Popguns, of course, and Dixie gains a gumball gun.
Blow You Away: The Snowmad leader's horn blows the Kongs off their island before freezing it.
Bootstrapped Theme: The initial E3 2013 trailers and gameplay footage frequently used the Jungle Hijinx theme, DK Island Swing, with the implication that it would be used in the opening Lost Mangrove levels. But later footage revealed that the Lost Mangrove levels would instead feature a new piece of music, which seems to indicate that DK Island Swing was used more to hype up the fans. It's instead used in the secret K levels, unlocked by getting every KONG letter in each world.
Boss Subtitles: Every boss has a title that is shown on their figurine. In order, these are:
Dixie Kong returns as the third playable character alongside DK, Diddy, and Cranky. Funky Kong is also back to take over Cranky's previous role as the shopkeeper.
A single type of enemy from the original trilogy (Puftup, the pufferfish from DKC2) returns in Sea Breeze Cove, appearing in Amiss Abyss, Irate Eight, and Shoal Atoll. He's been pretty heavily redesigned, but according to some supplementary material such as the official player's guide, that's really him.
Call Back: The first level begins with the player having to shake the controller before the gameplay begins for real, just like in the first level of the previous game.
Check Point Starvation: The K levels, as per usual. 4-B also qualifies, being the only regular level without checkpoints. The three levels in World 7, Secret Seclusion, also fit. Every level in Hard Mode also becomes this.
Fragile Speedster: Diddy Kong, who moves fast but is hard to control (especially underwater).
Lightning Bruiser: Dixie Kong, who can move fast (but at a controllable pace) and twirl in the air with her ponytails.
Mighty Glacier: Cranky Kong, who has not 1, or 2, but 3 attacks (not counting Goomba Stomping): his denture popgun (that functions like Diddy's), his roll, and his deadly Ground Pound attack with his cane that defeats almost all enemies and lets him hop on spikes. But he is also the slowest of the crew.
Continuity Nod: World 6, Donkey Kong Island, is filled with them for players of Returns.
In the first water area of the first level, diving completely underwater plays a updated remix of the water levels from Donkey Kong Country 1.
In the secret exit of 1-3, Canopy Chaos. You can find Cranky's Victrola from the intro to the original DKC, and it even plays the same tune.
Death Mountain: Autumn Heights. Instead of being rocky, these mountains have a forested, Bavarian flavor.
Derelict Graveyard: Lost Mangroves. A swampy island filled with shipwrecks and crashed planes.
Drop the Hammer: Bashmaster, the boss of Juicy Jungle, wields a giant hammer. It even generates ice shockwaves when he brings it down.
Easter Egg: In the plane at the beginning of Mangrove Cove, one can find a set of televisions that display the menu screen from Donkey Kong Country Returns if they are turned on. And that's barely scratching the surface... to cover just a few of them:
The gramophone at the end of 1-3 will play the original Donkey Kong Country theme if you pound next to it.
He's Back: David Wise, the composer of the original DKC trilogy, returns to compose for this game. He has since left Rare (the developers of the original trilogy, as well as Donkey Kong 64), and is now independent.
Limit Break: The Kong Pow. Collecting bananas gradually fills a gauge on the HUD that, when full, allows the Kongs to transform all onscreen enemies into extra lives, recovery hearts, or Banana Coins. It takes two characters to pull off the move, though, so Donkey Kong is out of luck if he's by himself.
Long Song, Short Scene: The famous Stickerbrush Symphony theme returns, but only plays at the beginning and end of a Rocket Barrel stage.
Mercy Mode: Averted. The Super Guide from the previous game is absent.
No Flow in CGI: According to producer Kensuke Tanabe, the developers decided to take advantage of the Wii U's power by averting this, despite highly increased development time. The E3 2013 reveal of the game saw Satoru Iwata making a special point of calling attention to DK's new fur physics.
No-Holds-Barred Beatdown: Much like the previous game, upon defeating a boss, you're treated to a little mini-game where Donkey Kong beats the boss to a pulp before sending them flying with a Twinkle In The Sky.
No OSHA Compliance: The juice-making factory in Juicy Jungle has unguarded tanks, exposed juicer blades, and animals swimming in the juice.
Our Dragons Are Different: The leader of the Snowmads uses a magic horn to summon / control a gigantic ice dragon. The dragon's icy breath freezes over Donkey Kong Island, turning it into a more suitable home for the Snowmads.
The Spiny: Snowmads with horned helmets will hurt you if you jump on them. Ditto goes for owls on fire and those flaming porcupines in the Savannah levels. Cranky's pogo cane bypasses the horns and allows him to kill them, but the fire enemies will still hurt him.
Variable Mix: A more relaxing, atmospheric version of a level's theme will play when you are underwater. In addition, a large amount of stages add more instruments as you go along.
World 2-6 (Wing Ding) has two versions of the track for when you're on the ground and zip-lining along the vines.
World 4-4 (Irate Eight) has four tracks playing throughout the level. One at the beginning, one while underwater, a remix of Lockjaw's Locker, and a tense theme played while being chased by the octopus.
Mountain Mania and Frantic Fields gain extra drums when you're riding Rambi.
Wolfpack Boss: Ba-boom, who splits into three individual baboons that attack you. Subverted by the last phase, where you can only hurt the one that isn't a "ghost".
Cranky Kong: Bah! You kids and your high-definition video games. Back in my day, we didn't have any definition!