Todd went clear, just picking up 6.8 time penalties, giving him a 0.2 point buffer ahead of Marina Köhncke (Germany) on Calma Schelly.
"Land Vision is a good horse but he's relatively young (10) and he did feel green," said Todd, whose last appearance in a CCI4* press conference was 12 years ago when he finished second on Word Perfect.
"He definitely felt tired after Huntsmans Close and I had to nurse him home, but he felt really genuine. I had to give him a bit of a shake-up in the Quarry but he picked up and that's the sign of a good horse."
Marina Köhncke who, coincidentally led Todd in the dressage back in 1994, could yet make history as the first German rider to win Badminton.
In a dramatic afternoon, she was held on course while officials attended to Louise Skelton (GBR) and Partly Pickled, who fell at the Sunken Lane (16). "I wasn't that cool about being held, because I don't do this (riding at 4-star level) that often!" said Köhncke.
"But everyone was telling me at the start that I had to go faster this time. Finishing so well at Badminton is a dream for me. It's fantastic to be back."
Pathfinder Andrew Nicholson (NZL), who is lying fourth on Nereo, gave a typically confidence-giving display to his peers, coming home seven seconds inside the optimum time of 11 minutes 15 seconds on Avebury, despite taking the long route at the Farmyard (fence 15). But the time proved much harder to achieve than predicted, with only seven of the 76 starters crossing the finish line penalty free.
Caroline Powell and Lenamore and Nicholson on Avebury are in 10th and 11th spots respectively, just 3.6 points behind the leader.
Andrew Nicholson and Nereo.
Oliver Townend (GBR), seventh, had a near-miss when Ashdale Cruise Master pecked in the Lake, and it was all over when the grey fell on landing over the third element of the Quarry (fence 27).
Aoife Clark (IRL), eighth, had a frustrating ealy run-out at the Hillside (fence 6) on Master Crusoe, and Susanna Bordone (ITA), ninth, lost her chance when Carrera tripped up the step out of the Lake and incurred 20 penalties.
Ingrid Klimke (GBR), equal 10th, was taken to hospital in Bristol for a precautionary look at her leg after Butts Abraxxas tipped over the second log element of Huntsmans Close. Selina O'Hanlon, on the same dressage score as Klimke, dropped out of the reckoning with two refusals at the Sunken Road (16).
After a horse fall at the same fence, Elizabeth Power (IRL) was also taken to hospital for a check-up after being knocked unconscious but was reported to be recovering well. She remained in hospital overnight for observation.
Eighty combinations started the cross country, which covered 6422 metres and included 30 obstacles, with just 60 posting scores - 12 were eliminated over the course, with six retiring.
There were, however, 50 clear rounds and 59 horses will go through to today's Jumping phase in what promises to be the most exciting finale ever.
The dramatic falls were a major blow to Irish hopes. As well as Elizabeth Power, Camilla Speirs was also taken to hospital. Sarah Wardell was automatically eliminated after she parted company with Killeenduff Boy in a fall at the lake, but although shaken, was not injured. All three horses recovered from their experiences on the course.
Aoife Clark (Ire) and Vaguely North. © Mike Bain
"However, Aoife rode really well after that and had a superb round on her other horse Vaguely North."
Ireland's Joseph Murphy, making his Badminton debut, improved his overnight position by 19 places to finish in 35th on the Cruising gelding Electric Cruise.
• HSBC Training Bursary
Flora Harris (GBR), lying 19th on Law Choice, is currently in line to win the HSBC Training Bursary - a unique award presented to the highest placed rider at each HSBC FEI Classics leg who completes a 4* event for the first time. The winning rider will be presented with an award and training voucher to the value of $1000 today.