Notes

Both are Possible

Here's the video. The launcher appears a little familiar however I don't believe three engines can work because the central engine will be too heavy in thrust to land! A boost-back burn can be seen.



What is your definition of "too much thrust to land"? I don't know of any theoretical upper limit. A higher minimum thrust and acceleration makes landing more difficult, but not impossible.



Theoretically, as thrust goes to infinity, the time needed to reduce the vertical velocity goes to zero. In a real-engine, there's a certain minimal time for startup+thrust+shutdown. Particularly if the turbopump is involved. The stage dry mass is the most effective source of landing engine thrust.



In addition, since we're likely to see the launcher to be 100 tons or more The engine will likely require a larger engine than the F-1.



First, F9 can use 3 out of 10 engines. In this context landing on one of three engines isn't unusual.
The titan launcher


Second, if you're planning to put forward an engine with infinite thrust you can also imagine an engine that has an infinite start up time. The two conditions are equally possible. Both aren't even close to what is really relevant here.


Website: https://titanlauncher.com/