Puzzle

 ACROSS

  1 Golfer's rental

  5 More cunning

 10 Tomato variety

 14 Texter's "Then again ..."

 15 Scott who played Princess Jasmine

 16 "Beowulf," e.g.

 17 Eventually enter the mind of + an ancient element = get real

 20 Symbolic American dessert

 21 Bluish gray

 22 Knowing, as a secret

 23 They provide insights about relationships

 25 Taking advantage of + an ancient element = elated

 29 Roswell crash victim, some believe

 30 Constantly remind

 31 "@#$%," for one

 35 Iodide, oxide or nitride

 36 Soda fountain treats

 38 Kind of sauce

 39 Caddie's bagful

 41 Mood music?

 42 Suddenly paid attention

 44 Handle idly + an ancient element = do something risky

 48 Descendants

 50 Cocktail at a Mexican restaurant, informally

 51 Forbidden City's country

 52 Guests' call at the door

 56 Inconsistent way to blow + an ancient element = standard sink connections

 59 Word before "the Rainbow" or "the moon"

 60 ___ Island

 61 Zilch

 62 Little sibling, perhaps

 63 "___ Marner"

 64 Coin opening

DOWN

  1 ___-Cola

  2 At the peak of

  3 Cakewalk

  4 Similar stuff

  5 Attach with a click

  6 Sneaker feature

  7 Oxen connector

  8 Ambulance VIP

  9 ___ de Janeiro

 10 Total expert

 11 Big name in book clubs

 12 "Paws"

 13 Advil target

 18 Neighbor of Nigeria

 19 Actor Morales

 23 Small, biting insect

 24 Riches' counterpart

 25 What many do at the DMV

 26 Burn balm

 27 One may be dotted

 28 Simmering

 32 Italian wine center

 33 Part of a campus visit, often

 34 Extravagant promotion

 36 Unkind

 37 Vegan Supreme Pizza brand

 40 Motion pictures?

 42 Molelike animal

 43 Knitted blankets

 45 Cash advance

 46 Marcos with many shoes

 47 "Buenas ___" (afternoon greeting in Acapulco)

 48 Rudely push

 49 Refers to

 51 Slice of pork

 52 Material in 43-Down

 53 Latin abbr. hidden in "set a limit"

 54 Second chance, informally

 55 The "E" in QED

 57 Many AMA members

 58 Part of a Greek X word

Solution