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