Psychic Energy My personal favourite especially as Ive used and fine tuned a not-at-all tournament legal Deoxys deck with Nidoking and Nidoqueen support, which is on its latest iteration after having first been built close to twenty years ago of all the basic Energy types is Psychic Energy
Blacksmith's Skill One of the most efficient protection spells out there, Blacksmith's Skill is an instant that saves any permanent, not just creatures, from targeted removal or destruction effects
Better yet, once Cloud attacks, you draw a card for every equipped attacker, and possibly make Treasure tokens if their power hits 7 or more
This will actually finish off an opponent immediately as Vorinclex will cause Vraska to generate twice as many poison counters, giving an opponent with none 18, rather than nine
Changing pace a bit, you have Elsha, Threefold Master to go more in the token approach