Taking over with your long suit in no trump (declarer's view)
'Me' at the bottom is the viewpoint player; P2–P5 are the other four seats.
Setup
Mighty Basics Replay. This game is from the declarer's view: cashing a long suit all the way in no trump. I won the bid at ♥18, then switched to no trump, raising the contract to 20. No trump means there is no trump suit, so no ruffs; the highest card of the suit led wins. My long suit is five hearts, and I also hold the Mighty and the Joker. P3, holding the Friend card ♥A, is my Friend.
Trick 1
I led my lowest heart, the ♥3. The ♥A is in my Friend's hand, so this low lead is a call for help to the Friend. My Friend took it with ♥A and revealed themselves.
Trick 2
My Friend first cashed the boss ♣A. With no clubs, I dropped my only diamond, the ♦5, to tidy my hand.
Trick 3
My Friend returned the heart I asked for, with the ♥8. With ♥A gone, my ♥K is now the boss. I took the ♥Q along with it and got the lead back.
Trick 4
I continued with the ♥J. All the higher hearts are gone, so the ♥J is the boss. Counting cards, the only hearts left are my ♥10 and ♥5 — both sure winners.
Trick 5
On my ♥10 lead, my Friend, out of hearts, loaded the ♣10. The defenders have no trumps to ruff with, so they can't stop it.
Trick 6
Even the ♥5 wins. A low card becomes the boss of its suit once every higher card is gone. P5, left with only honors, had to give up the ♦10.
Trick 7
With the hearts used up, I moved on to spades. When I led the Mighty, P2 had to follow with ♠K and P5 with ♠Q. Three points from one Mighty.
Trick 8
This time I led the Joker and called spades. My Friend played ♠J and P4 ♠10, and all the high spades outside were gone.
Trick 9
The only spades left are my ♠9 and ♠7, so the ♠9 is the boss too. In no trump a void isn't a ruffing weapon, just a place to discard, so the defenders could only throw away honors.
Trick 10
My last spade, the ♠7, won as well. The defenders held ♦A and ♣K to the very end, but without the lead they never got to use them.
Result
20:0, a run. With no ruffs in no trump, whoever holds the lead can press all the way to the end. The trick in no trump is to count the remaining cards and know when a low card becomes the boss. You can step through this game yourself in the Basics Replay section of Mighty Korea's school (mightykorea.com).