Orcs Must Die! 2 skull upgrades, replay goals and Endless mode
Improve a focused loadout and revise it for the next map.
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Edition covered
Original Orcs Must Die! 2 campaign and core systems. DLC-only traps, maps and enemies are not required; mechanics from Orcs Must Die! 3 and Deathtrap are excluded.
Separate map currency from skulls

The money earned within a map buys placements during that run. Skulls support persistent purchases and upgrades between runs, so spending one does not serve the same purpose as saving the other.
| Resource or goal | Use | Decision |
|---|---|---|
| In-map money | Place defenses in the current run | Spend on the next wave's needs |
| Skulls | Persistent unlocks and upgrades | Improve a coherent loadout |
| Level rating | Measures completion performance | Replay after fixing the weak point |
| Score | Rewards effective kills and combos | Pursue after the layout survives |
Upgrade the core of the layout
Invest in the traps and weapons that do most of the work on the next map. A broad collection of unupgraded tools may be less effective than a smaller loadout with a clear plan and the necessary special-enemy counters.
| Mode or goal | Focus | Preparation |
|---|---|---|
| Campaign | Complete the level's waves | Learn its doors and enemy types |
| Co-op | Coordinate two heroes | Agree on lanes and shared trap plan |
| Nightmare | Handle a harder challenge | Use a practiced efficient setup |
| Endless | Survive escalating waves | Plan heavy-enemy and air coverage |
Replay with a specific improvement
Use a replay to fix the route that leaked, improve timing or pursue a better rating. Compare the actual result rather than changing every trap simultaneously and losing track of what helped.
Build Endless defenses for maintenance
Long runs expose weak anti-air, heavy-enemy damage and barricade protection. Keep the layout readable and leave the hero a route between threatened lanes so later waves do not trap you away from the rift.
References
| Reference | Website |
|---|---|
| Publisher game and edition listing | store.steampowered.com |
| Robot Entertainment game reference | robotentertainment.com |



