Recently Ferdinand Mosca, author of Deuterium released a first beta version of NUCLEUS a tool that got hardly any attention hence this special ProDeo version that will try to introduce the nice things you can do with it and make it more user friendly.
In a nutshell, NUCLEUS is an engine adapter that can take 3 engines as a single engine. It will run slave1 and slave2 engines to determine the best move of the position, then run the master engine to decide which best move will be selected, either from slave1 or slave2. See further in the README file in the NUCLEUS download .
In this ProDeo 2.7 version NUCLEUS is included and contains 8 pre-installed engines which you can mix as either master or slave, any combination is possible, see below pictures. The default setting is that ProDeo 2.7 is the master engine and Stockfish 9 and Sting 9.9 are the 2 slaves.
As for a small example consider this position:
2r1rbk1/p1Bq1ppp/Ppn1b3/1Npp4/B7/3P2Q1/1PP2PPP/R4RK1 w - - 0 1 bm=Nxa7;
Normally ProDeo needs 15 seconds to find Nxa7, Stockfish does not find it in 2 seconds and wants to play Rfe1 instead, but Sting does. So ProDeo as the master and arbiter (also having just 2 seconds) has to decide to make a choice between Rfe1 and Nxa7. And in this case Sting has been extremely helpful, ProDeo plays Nxa7.