In theory there is no limit to what an attack pattern can be like. They can be as big and have any shape CipSoft wants them to. When designing a creature and its spells, they can draw any pattern they want. Furthermore, any spell can in principle be used on the target or on "itself", though direction attacks (waves, beams) don't make much sense on target.
Recently, CipSoft has also implemented attacks that last more than one turn. For example, Malofur Mangrinder's BOOM becomes larger and stronger each turn. King Zelos' Death and Blood rings start small and grow larger for a few turns. Even though these aren't shapes per se, they are important mechanisms to know when fighting these bosses.
That being said, we can name some common and other more unusual patterns:
- Circles: this pattern is used for "bombs", "balls" and "UE" attacks. These range from small circles with 3 tiles of diameter to large Gaz'Haragoth-like UEs with about 15 tiles of diameter. Not all Circles are identical though, and there may be differences on which tiles on the edges are filled even if the radius is the same.
Lady Tenebris' death UE
- Beams: also a very common pattern, this consists in a straight line in front of the attacker, which can have a small (3) to very long (10) length. Many creatures and bosses uses it, one classical example being the Demon's Life Drain beam.
Prince Drazzak's death beam
- Waves: Also very common, these are cone-shaped attacks in front of the attacker. The cones can also have many different lenghts, from Dragon's small (4?) wave to The Duke of the Depths huge wave. How wide the cone is varies from spell to spell.
The Duke of the Depths' Fire Wave
- Berserks: these can be seen as a special case of the Circle pattern, or maybe a small square pattern. It deserves a special mention though since "Berserks" are usually named when they are used by the creature on the same tile they are on, only hitting those directly close to it. The name comes from the classic Knight spell.
Haunter's energy berserk
These are probably the most common patterns used by creatures and bosses, but like I said, anything is possible. Other used patterns are:
- Rings: a ring is just the outer edge, the perimeter, of a circle. It has the distinctive characteristic of hitting players far from the creature but not near it, despite being centered on the attacker. It's used by Burning Gladiators and King Zelos, for example.
King Zelos' growing death ring.
- Cross: shaped like a + sign, a cross is easy to imagine. There are small cross-attacks used by some creatures such as Priestess of the Wild Sun, though an impressive one that comes to mind is Plagueroot's and its classic attack, a room-wide cross that deals very high damage.
Plagueroot's cross earth attack.
- X-shaped: similar to a small cross, but on the diagonals instead. Creatures that use this attack include Burning Gladiators and Priestess of the Wild Sun.
Priestess of the Wild Sun's X fire on target. Source: https://www.youtube.com/watch?v=gYV_aKuobLY
- T-shaped: This distinctive pattern is the classic attack of Abyssador, the Warzone 3 boss.
Abyssador's T-shaped attack. Source: https://www.youtube.com/watch?v=OSMH8rhPc5o
- Chain attacks: this is not exactly a shape, but a recently implemented type of attack. Instead of having a fixed shape, these attacks chain through characters that are near each other, starting at the target. This type of attack was initially only used by bosses, but recently implemented creatures such as the Mould Phantom also use it.
Lifesteal chain (looks like sparks) hitting all players. Used by Alptramun.
All images are from videos I recorded myself, except where a source is given.