12 - Summon skulls : impulse 102

11 - Walk upside down : cl_pitchup 360
cl pitchdown 360

10 - Do giant jumps : sv_gravity 300

9 - Add a bot "mirror" : bot_add_t or bot_add_ct
bot_mimic 1

8 - Summon chickens : ent_create chicken or
give chicken

7 - Show the bullets impacts : sv_showimpacts 1 or
sv_showimpacts 2

6 - Vanilla Wallack : r_drawothermodels 2

5 - Thirdperson : thirdperson (if you want to be in firstperson tip firstperson)

4 - wallack and slow motion : host_timescale 1
host_timescale 0.5

3 - Giants guns : ent_fire weapon_ak47 addoutput "modelscale 10"
ent_fire weapon_awp addoutput "modelscale 10"

2 - Be IronMan : r_showenvcubemap 1

1 - Be rightanded or lefthanded : cl_righthand 1
cl_righthand 0