By Alex Rosenthal

The solver is presented with two images of heads, and thirty-three TIL statements.

It’s possible to transdelete a word in each statement to make it true. For example, “A man began to hiccup after a goth fell on him, and he wasn't able to stop until 68 years later.” GOTH = HOG + T.

All of these statements are facts that can be found within TED-Ed videos. The thirty-three cells within the first image of the head all contain stills from those same videos. Identify them. The head image can be found at the beginning of every TED-Ed video.

Place the added letters from the TIL’s into the second image of the head, in the corresponding spot to the still from that video. For example, the lower left still is from the video “Could we actually live on Mars?”. The added letter in that video was a T (TRAMS = MARS + T), so place a T in that spot in the second head image.

Reading off the thirty-three letters in the order suggested by the black dots between cells in the second image yields the clue phrase: TIL HANDS CAN COUNT USING BIRYANI AT END.

Iterate on the transdeletion technique to get TIL HANDS CAN COUNT USING BINARY AT END.

This is a reference to the TED-Ed video “How high can you count on your fingers?”. At the end of that video (at time 3:57), solvers will find thirteen hands around a computer chip, cycling through a sequence of binary finger positions. Either by pausing, or focusing on an individual hand going through the full sequence, solvers can translate the binary into decimal, then into letters (00011 = 3 = C), yielding the answer CRANIOGRAPHER.

TIL On TRAMS (MARS + T), you could expect to watch spectacular blue sunsets in the normally red sky. TRAMS MARS T YouTube
TIL One group of bottlenose dolphins off the Australian coast has learned how to put PIGEONS (SPONGE + I) on their rostra when rooting in sharp corals. PIGEONS SPONGE I YouTube
TIL Ancient Egyptians used to pee on WEALTH (wheat + L) as a somewhat reliable test of the genders of their unborn children. WEALTH WHEAT L YouTube
TIL You can shed three different types of HATERS (TEARS + H). HATERS TEARS H YouTube
TIL Throughout the course of history, the global percentage of FEALTIES (LEFTIES + A) has hovered around 10%. FEALTIES LEFTIES A YouTube
TIL It takes light 170,000 years to leave the NUNS (SUN + N). NUNS SUN N YouTube
TIL that ENFIELD (FELINE + D) purrs may have healing powers. ENFIELD FELINE D YouTube
TIL London may run out of RAILBUS (burial + S) space by 2035. RAILBUS BURIAL S YouTube
TIL NARCISSUS (RUSSIANS + C) and Americans once almost initiated a global nuclear apocalypse, but the world was saved by a man named Vasili Arkhipov. NARCISSUS RUSSIANS C YouTube
TIL Extreme heat PROCREATES (RECEPTORS + A) in your mouth are also triggered by spicy food. PROCREATES RECEPTORS A YouTube
TIL In 2014, a devoted soccer fan DINED (DIED + N) after staying awake for 48 hours to watch the World Cup. DINED DIED N YouTube
TIL A single MECHANIC (Machine + C) could colonize the entire galaxy in just 4 million years. MECHANIC MACHINE C YouTube
TIL The Homeric villain CICERO (Circe + O) may have been an accomplished chemist. CICERO CIRCE O YouTube
TIL Michael ADJOURN (JORDAN + U) at his prime could have dunked from behind half-court on the moon, with a hang time of 5.5 seconds. ADJOURN JORDAN U YouTube
TIL Gold comes from PECANS (SPACE + N). PECANS SPACE N YouTube
TIL A man began to hiccup after a GOTH (HOG + T) fell on him, and he wasn’t able to stop until 68 years later. GOTH HOG T YouTube
TIL The Greek colony of AUDIOTAPE (POTIDAEA + U) was once saved by either an act of nature or Poseidon (depending on whom you ask). AUDIOTAPE POTIDAEA U YouTube
TIL The first 13 Olympics only had one STEVEN (EVENT + S) STEVEN EVENT S YouTube
TIL Most clouds don’t float; they slowly FLAIL (FALL + I) to earth under the influence of gravity. FLAIL FALL I YouTube
TIL Van Gogh’s RANT (ART + N) unintentionally modelled one of the most complex phenomena in physics. RANT ART N YouTube
TIL There are almost zero GLEAM (MALE + G) Whiptail lizards. GLEAM MALE G YouTube
TIL The name of a certain small, stringed instrument means jumping FABLE (FLEA + B) in Hawaiian, despite the instrument not actually originating in Hawaii. FABLE FLEA B YouTube
TIL Chronic SISTERS (STRESS + I) can change the size of your brain. SISTERS STRESS I YouTube
TIL You can write a valid sentence just by repeating the word NARC (CAN + R) over and over. NARC CAN R YouTube
TIL The Lion’s MEANY (Mane + Y) jellyfish has tentacles that can extend longer than a blue whale. MEANY MANE Y YouTube
TIL Monkeys, apes, bats, humans, and elephant WASHERS (SHREWS + A) are the only mammals on Earth that menstruate. WASHERS SHREWS A YouTube
TIL Early examples of TARIFFING (GRAFFITI + N) could be found in Ancient Rome, Mayan cities, and Pompeii. TARIFFING GRAFFITI N YouTube
TIL Neutrinos make it possible to detect exploding SITARS (STARS + I) before their light reaches the earth. SITARS STARS I YouTube
TIL The philosopher TAPALO (PLATO + A) believed that a woman’s womb was a live animal that could wander around in her body and cause illness. TAPALO PLATO A YouTube
TIL Baleen whales sing using large inflatable SCATS (SACS + T). SCATS SACS T YouTube
TIL A popular exercise machine was invented to torture british REPRESSION (PRISONERS + E) REPRESSION PRISONERS E YouTube
TIL It’s possible to WRONG (GROW + N) bones outside the human body. WRONG GROW N YouTube
TIL Ocular DEFLATORS (FLOATERS + D) are made of bits of tissue, red blood cells, or clumps of protein. DEFLATORS FLOATERS D YouTube