Add truffle test for each level's contract - [ ] level 0 - [ ] level 1 - [ ] level 2 - [ ] level 3 - [ ] level 4 - [ ] level 5 - [ ] level 6 - [ ] level 7 - [ ] level 8 - [ ] level 9 - [ ] level 10 - [ ] level 11 - [ ] level 12