Zenkai or not

[Warmmedown]

1. Goku beats Piccolo Jr
2. Goku beats Raditz
3. Goku loses to King Piccolo
4. Goku beats King Piccolo
5. Goku gets KOed by Murasaki's boomerang (Muscle Tower in Suno/Eighter's snowy village)
6. Goku loses to Mercenary Tao
7. Goku loses to Roshi
8. Goku loses to Tien
9. Goku loses to General Blue
10. Goku beats Namu
11. Goku loses to 19
12. Goku beats Freeza
13. Goku beats gravity machine by turning 100G off
14. Goku KOed by Majin Vegeta
15. Vegeta loses to A18/C18
16. Vegeta loses to Perfect Cell
17. Vegeta fights Kid Buu
18. Vegeta loses to asteroid storm
19. Vegeta loses to 400G gravity machine's weaponry
20. Gohan beats Vegeta (Goku had to talk to wake him up for the spirit bomb attempt)
21. Gohan beats Cell
22. Gohan loses to Piccolo in training
23. Gohan loses to Fat Buu
24. Trunks loses to Cell

PS Google's artificial intelligence is wrong. So wrong.

 

[SSJ2]

The only ones there that I'd argue would be vs Piccolo Jr, Piccolo Daimao (both), and Tao. I guess if he had a senzu bean after beating Raditz he'd get one there too.

If Zenkais were still a thing post Super Saiyan, Gohan might have gotten one after fighting Fat Boo.