Structural Cover
Just about every piece of cover on Warlock is part of the structure of the map. Sight lines are broken by geometry that is also a functional area on the map, not a random crate sitting in the middle of an open field. While “lazy cover” can be a viable option in certain scenarios, like the rock gardens on Sanctuary, it is generally better to block sightlines with structural cover like Sanctuary’s central ring-structure. Placing a large structure in the center of a map is a simple way of blocking many cross-map sightlines.
Elevation Change
The convex curvature of the top bridge on Narrows demonstrates how elevation change can act as a sight line blocker. Elevation change also creates more playable space without increasing the X and Y axis dimensions of the map. In addition, elevation change creates a more dynamic experience for the player than if he was always moving on the same, one or two, elevation levels like on Haven.
Vertical Overlap
Both Warlock and Narrows allow different players to occupy the same X and Y coordinates with the only variable, between their positions, being the Z coordinate. Since players cannot see through the ground beneath them, or through the ceiling above them, vertical overlap acts as a vertical sight line blocker. In addition, vertical overlap creates flanking routes that help prevent the map from playing too linearly, like Station 9. Players can trade the benefits of top control for the opportunity to surprise their opponent by approaching from an unexpected angle.
Lockout is a good example of how vertical overlap can increase the playable space on a map without increasing its overall X and Y axis dimensions. While vertical overlap generally increases the strength of top control, it also allows map creators to place skill based “tac jumps” that give players the opportunity to increase their vertical mobility. Tac jumps can allow players to move vertically, from a low position to a high position, without traveling a long horizontal distance; like traveling up an elevator instead of traveling up a spiral staircase.
Vertical Interplay
Unlike Warlock, which provides players with many opportunities to engage enemies on a level above or below them, a player on one of Haven’s streets or basements is fairly restricted to that specific level. Where a player on one of Warlock’s plats could drop down to finish off a fleeing enemy, the transition on Haven heavily rewards the player who dropped first because the second player is dropping into a cubby-like closet area that provides little room to maneuver, no option for escape, and can be easily grenaded.
On Warlock, where a player could drop off any side of any plat, the ability to fluidly transition from high to low is infinitely higher than on Haven where you are either taking one of four cardinal ramps or one of five specific drop downs. Lack of vertical interplay causes maps to feel like all “hallway battles” and forces players to commit too strongly to a specific path.