The Mana harvesters are a creation made by the collective research acquired by a so called Dr. Omer Pritchett (if that is fine with you I am wanting to have Omer elimanted by this creation). They are inability to hide has allowed us to collect data on them. While stages have been seen it is at random at what these creatures select in these stages. It also appears that these creatures use pure mana and have an ecttodinarliy flexible mana pool.


Stage 0: The Mana harvester is in its default stage. Its right forearm and hand a grotesquely burnt and mis-shappen while able to hide if touched while cause immediate alarm to the creature.
                                -In this stage the mana harvester will usually have a weapon of its own. Whether that be a sword gun or rifle it varies but they use this to cause a near death state in which the harvester places their hand on the chest of the victim draining their mana with a spell imbued in their arm. They use this spell to transfer energy to the runes and gems embedded in their back. After analysis it is seen that these have been fused to the bone and would kill the subject if removed causing a mana overflow.
Runes observed appear to be spells. However they are formed in such a way that unless extensive work is done to capture a live example they are unable to be deciphered as they decay at an alarming rate.

Stage 1: After a suffcient amount of mana has been acquried ussaly 750 to 1175. A rune will glow on their back. This rune gives them an opportunity to forcefully change their body into a form more situated to the situation.
                                - The current rune activation observed at this stage are the significant increase in muscle mass. Giving them the ability to push back soldiers several yards and cause heavy damage to even the thickest personal armor. That or the formation of a blade on the left hand. This blade has been observed cutting through 3 inch steel doors and working through trees like they were paper indicating that this growth that has the ability to change in future stages is extraordinarily sharp.
                                - It has also been observed that these creatures go into a moment of shock as the use the mana in the rune. It is unknown if this is to avoid a mana overflow or not. More study required.

Stage 2: It is unknown if another stage 1 rune can be used at 1 time but in stage 2 more mana has been absorbed from victims 1850 to 2250. This triggers another rune to light up.
                                - The creature now has the choice it appears between 3 items. their legs could recede into their body and 8 spider like legs can protrude out of the back 2 of which are razor sharp and 2 are barbed to grab and maul anyone who falls prey. The remaining 4 allow for heightend movement and the ability to scale walls. The second is in where the jaw unhinges revealing a much sharper row of teeth and a elongated toung capable of grabbing and dragging victims towards the mouth. The final possibility is the protrusion of wings allowing the creature sustained flight making shots harder to land.
                                - At this stage the right arms features start to spread affect the shoulder and part of the upper torso  and lower neck.
                                - It has also been observed that more than 1 of stage 2 runes can be used but only 1 type of movement change. This requires an additional 1125 mana it appears.
Stage 3: this is the furthest stage ever reached and their is only 1 high cost rune on this stage. It has been observed that 2 more stages are available but they avoid using them for unknown reasons. This stage seems to require a massive amount of mana 4500 acquired after stage 2
                                - The size of the creature quadruples and heightens the creatures abilities to an extraordinary level. this ability allows the creature to have a higher chance of avoiding them or locking 4 or more people excluding itself in a state of time freeze. Mana will build up and the creature able to use a multitude of magics that it has learned outside of its current stages.
                                - Their appears to be a weak point on the back side of its neck  only accessible by anything with the ability to fly.


Stage 4: (not a change just secondary runes) It is possible that the runes known underneath stage 3 are used for healing purposes. the creature will halt in place and be surrounded by a rock barrier as wounds heal shut. If both runes are not lit up then 1 or the other ability is unable to be used.