What are some weaknesses of a Yugioh Warrior-type deck?

Answer 1

Decks that focus specifically on the Warrior-type have many benefits; if those benefits were to be minimized or even put to a halt, the deck would crumble.

Warriors need to be able to build up field presence. On their own, many Warriors like "Command Knight" cannot do much. In order to accomplish this, these decks often include cards like "Reinforcement of the Army" and more to search their decks or Graveyards for Warriors to use. "Thunder King" stops those efforts dead in their tracks because with him on the field, cards can only be added from your deck to your hand during the Draw Phase. Other means of getting Warriors out include "Giant Rat" and other effects that Special Summon. "Royal Oppression" can stop some of these, but not effects that activate during the Damage Step like "Giant Rat". The simplest and easiest way to deal with this is to destroy these monsters via card effects. I'm talking about "Icarus Attack", "Mirror Force", "Torrential Tribute", "Lightning Vortex", "Dark Armed Dragon" ("DAD"). Cards like these put a dent in a Warrior deck's efforts to build up their field and win via Syncro Summons and/ or power monsters.

Other misc. means of dealing with Warriors include simply having "bigger" monsters. In battle, some Warriors do boast reasonable ATK, but other than that, simple battle can eliminate them. That being said, a reasonable Warrior deck would include a variety of methods to boost their monsters' ATK like "Shrink", Equip Spell cards, etc.; be careful of the duelist's back row.

Also watch out for Warriors' nasty effects. "Exiled Force" is a dangerous card and with many ways of recycling Warriors, can be a recurring problem. "Goyo Guardian" and "Colossal Fighter" are two immense Synchro Monsters with devastating effects. Timing is crucial here, you must ask yourself how will you deal with the Tuners because you could end up wasting cards if your opponent is able to retrieve more copies of the card. Keep in mind that without Syncros, Warrior-themed decks will not survive in the Synchro Summon-dominating-gameplay of today.

Keep in mind these tip are more centered on decks specifically geared towards Warriors. There are many decks that use a lot of Warriors like some "DAD" decks, but these tips do not amount to much against those decks - their weaknesses are simply different.