The captured Walls page contains only the upgrade-requirements table plus navigation and comments -- no descriptive intro, milestones or feature-unlock list. From the table, the Walls are Keep-gated strictly 1:1 (each level requires the matching Keep level, Lv1 Keep 1 ... Lv50 Keep 50). Costs are F/L/S/O with Stone/Ore entering at higher levels; construction-speed bonuses begin at +30% (Lv18) to +610% (Lv50). Power scales steeply from 21 at Lv1 to 146,000,000 at Lv50 -- the Walls are one of the largest single Power contributors in the base. Their defensive role is implied by name and cross-references (the Watchtower notes scouting reveals a target's Walls HP; a user comment asks about Wall Repair cost and HP) but this page does not state wall HP, repair rules, or any level that unlocks a function. For a bot, treat Walls as a Keep-gated Power/defense building leveled in lockstep with the Keep; specific defense values are not on this page. Whether upgrading disables any wall function is not addressed (unverified; other pages note Wall repair can be disabled mid-upgrade). [VERIFY] wall HP/repair mechanics from the game.
Original research source: Evony Guide Wiki