Here is the full list of all 20 Samurai vs Zombies Defense (Windows) achievements worth 200 gamerscore.
Get one wave up to level 99
Beat a wave using only farmer and swordsmith
Complete all 50 Waves
Kill the Demon Shogun
Kill 250 undead with the Katana Wave ability
Launch 1000 pachinko balls
Kill the Jorogumo
Summon Every possible unit
Upgrade 25 archer with the rifleman
Upgrade 25 farmers with the swordsmith
Complete 25 Waves
Save up 15,000 coins without spending it
Kill 50 chochinobake
Kill 50 Oni
Kill 100 undead with the katana slash
Revive yourself with a Charm
Complete 10 waves without allowing any damage to the Gate
Beat a wave without attacking
Beat a wave without summoning allies
Get all 50 waves to level 99