Low Level Deck

A Low Level Deck is one that only involves low level monsters (4 or lower, though level 3 is optimal for this design), and usually focuses on some of the more powerful effects rather than actually attacking to overwhelm your opponent. Closely related is the Low ATK Deck which is escentially the same, but can also include higher level monsters that have low attack, usually under 1000, though less than 1500 can also be considered low. Both use a similar strategy of getting otherwise weak monsters, usually Flip Effect monsters, on the field and activating their effects in order to clear your opponent's field of monsters and then attack directly.

There is a variant of this that uses Normal Monsters with support cards that only target Normal Monsters. This includes the Ojama monsters and their various support cards.

Monsters

 * Relinquished, of course, can be the single most important card in a low level deck, as its ability takes away one of your opponent's monsters, prevents it from being destroyed, AND deals damage to your opponent if they attack while a monster is equipped to Relinquished. In Traditional Format, its Fusion, Thousand-Eyes Restrict, is even better since it prevents enemy monsters from attacking.
 * Sangan or (in Traditional Format) Witch of the Black Forest for searching your deck for other low attack cards.
 * Chaos Necromancer will most likely get a very high attack boost late in the game, as most of the player's monsters will get destroyed.
 * Muka Muka and Infinite Cards is a nearly indespensible combo.
 * Two Ultimate Baseball Kids and any other Fire Attribute monsters to increase their attack by 1000 ATK for each Fire monster on the field. DNA Transplant can be used to augment this further.  This works especially well with a powered-up Raging Flame Sprite.
 * Raging Flame Sprite is a powerful card to use, especially with Swords of Revealing Light and Axe of Despair or Mage Power equiped to it.
 * Armed Ninja and Crimson Ninja can be used to destroy face-down Spells and Traps, respectively. For marginally higher ATK/DEF, replace Crimson Ninja with Trap Master.
 * Copycat can imitate much high level monsters if played correctly, potentially making it one of the most powerful options in this kind of deck.
 * Jinzo and other cards that can attack your opponent directly.

Spells

 * The Shallow Grave is excellent for bringing back Flip Effect monsters to reuse their abilities. An unlimited combo can be created by combining this with Magician of Faith, as its effect will allow you to bring back The Shallow Grave whenever it is destroyed, and the The Shallow Grave can be used to summon her back to the field during your next turn.
 * Swords of Revealing Light, above any other type of deck, is almost a requirement to make this work.
 * United We Stand, Mage Power, and Axe of Despair are powerful equips that can make a low level monster more capable of fending for itself. Megamorph can work very well in conjuncture with these.
 * Level Limit - Area B, Messenger of Peace, and other stalling cards.
 * Flint or Ekibyo Drakmord can be extremely helpful at preventing your opponent from destroying your monsters.

Traps

 * Gravity Bind can be used for an effect similar to Limit Level - Area B.
 * Reinforcements and Castle Walls are good for preventing monsters from being destroyed, if they are high enough of a level.
 * Magic Cylinder, Mirror Force, and similar cards can be used for redirecting damage back at your opponent.
 * Sakuretsu Armor can help open up your opponent's line of defenses for an attack, and is especially good at getting rid of very powerful monsters.
 * Gift Card can keep your Megamorph from cutting your monster's ATK in half, as well as ensure Raging Flame Sprite enough ATK to finish of your opponent quickly.
 * Forced Back and Compulsory Evacuation Device can keep high level monsters from being summoned to your opponent's side of the field.
 * Even the All-Powerful Exodia the Forbidden One is made up of cards with levels 3 and lower. And the most powerful one is only 1000 ATK and DEF!

Low ATK Only
You can also include a few other comboes if you go with low ATK only, as many high level cards with increadible effects exist that have less than 1000 ATK.


 * Winged Kuriboh, Transcendent Wings and Winged Kuriboh LV10 can devestate an opponent later in the game, as they will most likely have high-level monsters since most of your monsters will be used as shields.
 * Nobleman-Eater Bug and Hade-Hane for destroying monsters on the field or returning them to their owner's hand. For higher attack
 * A combination of Destiny Hero - Defender and Dreamsprite can prevent an opponent from attacking, as D. Hero Defender has a DEF of 2700, higher than the ATK of many high level monsters.
 * Skull-Mark Ladybug can be helpful, as its effect can be activated in response to battle or card effects that destroy it.
 * Since Hayabusa Knight can attack twice in a turn, powering it up with Equip cards can make it one of the most versatile cards available.
 * Millennium Shield and Labyrinth Wall both make good shields with high DEF and no ATK.
 * Aitsu, Koitsu, Soitsu, and Doitsu can make a great combo as well. By sending Koitsu or Doitsu to the Graveyard and using Call of the Haunted or Premature Burial to bring them back to the field, they can then be equiped to Aitsu or Soitsu, which destroys the cards used to summon them without destroying the monsters, as they are now considered Spell Cards.  Additionally, having both Union Monsters equipped gives you two monsters, one with 3000 and another with 2500 ATK, equivalent to a Blue-Eyes White Dragon and a Dark Magician!