ILLEGAL: R a1 - @; I - i1 on turn 2:
The coordinate @ is unknown in move MOVE: R a1 - @.
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For diagnostic purposes, here is the full movelist:
1. P d2 - d4 
1... n g8-f6 
2. R a1 - @; I - i1 
2... r a8 - @; i - i8 
3. P e2 - e3 
3... p e7-e6 
4. I i1 - c4 
4... p d7-d6 
5. I c4 - a8 
5... i i8-e7 
6. P g2 - g3 
6... i e7-b1 
7. I a8 - @; A - i1 
7... i b1-@; a-i8 
8. N g1 - f3 
8... a i8-b4 // Check!
9. B c1-d2 
9... a b4-a2 
10. A i1-b5 // Check
10... n b8-c6 
11. Q d1 -a1 
11... a a2-d5 
12. B f1-g2 
12... b c8-d7 
13. B d2-a5 
13... n c6-a5 
14. N f3-h4 
14... a d5-b4 // Check
15. K e1-d1 
15... b d7-b5 
16. P c2-c3 
16... a b4-d3 
17. Q a1-a5 
17... r h8-@; d-i8 // Pocket Rook and mutate to SuperBishop
18. B g2-f1 //ARGH!!!
18... d i8-c2 // Checkmate!