cut, pollute, degrade, lace, water down, distort, taint, weaken, contaminate, doctor, tamper with, mess around with, spike, bastardize, debase, adulterate, monkey around with, interfere with

cushion, suppress, kill, mute, dull, muffle, stifle, silence, blunt, dampen, deaden, numb, cool (down), stultify, quiet, desensitize, develop a thick skin, inure, accustom (someone to something unpleasant), suck the soul out of, insensitize, enfeeble, deafen

smash, wallop, flatten, level, demolish, bulldoze, shatter, destroy, gut, obliterate, cripple, wipe out, decimate, eradicate, annihilate, lay waste, reduce (to rubble), stamp out (opposition)

mangle, wallop, blindside, dislodge, degrade, compromise, paralyze, threaten, blot out, weaken, contaminate, subvert, derail, impair, doom, cripple, disable, damage, shut down, corrupt, upset (the apple cart), reduce (to rubble), stamp out, uncork, fray

drag, sag, die, age, fade, wane, die down, peter out, ebb, subside, sputter, weaken, melt, lapse, decline, teeter, wither, flag, fizzle out, fade away/out, abate, wind down, tire, lose ground, waste away, wilt, burn out, grow old, lose steam, taper off, gutter

oust, topple, dismantle, knock down/over, compromise, unseat, sabotage, subvert, impair, undermine, ruin, doom, defeat, cripple, damage, conquer, displace, take down, undercut, overturn, lay waste, rebel, defy, depose, revolt, overthrow, bring down, rise up, remove (from office/power), strip of (power/resources), dethrone, mutiny