Wolverines claws
This is a scenario set up in a post apocalyptic time. Each character becomes an enemy of the X-men, and the victory conditions are simple: After 100 encounters, if Wolverines fails to break his opponents weapon, he loses.
Otherwise, each encounter is assumed to be even, and to end in a tie. This is only to see what kind of metals can make a good "anti-adamantium" option, in that they can parry/survive multiple attacks from his claws and be useable for the long haul (As you'd need in a post apocalyptic setting.)
So, getting started:
0. Surgical steel katana.
1. Slade Wilsons sword.
2. Slade Wilson's staff.
3. Secondary adamantium sword (Say, used by Taskmaster).
4. Omega Reds armor.
5. Collleen Wings sword, infused with chi by Iron Fist.
6. Nth metal sword.
7. Battarang (Say, from whatever he can carry on his body. Remember, Batman can't make any more of those.)
8. Prometheum armor. (Should be stronger then sword and staff.)
9. Inertron shield.
10. New God sword.
11. Amazon sword.
12. Majestic's sword.
Finally, what is the bare minimum you'd need to take on primary adamantium weapons? Assuming Street/Meta (Logan level) users? Can it be done with conventional metals?