Breakdown of Além de teres agilidade sobre-humana, também podes voar.
também
also / too
ter
to have
poder
can / may (verb)
voar
to fly
Questions & Answers about Além de teres agilidade sobre-humana, também podes voar.
Why do we use the personal infinitive teres here instead of the regular infinitive ter?
The phrase além de (in addition to) ends in a preposition, and in Portuguese, prepositions are frequently followed by the personal infinitive. By conjugating the infinitive to teres, we explicitly show that the action of having belongs to the informal you (tu).
Since the main verb podes already tells us the subject is you, couldn't we just use the uninflected infinitive ter?
Grammatically, you could use the impersonal ter because both halves of the sentence share the exact same subject. However, native speakers highly prefer using the personal infinitive after prepositions like além de or apesar de even when subjects match, because it makes the phrasing sound more rhythmic and explicit.
Is the word também mandatory in the second half of the sentence?
It is not strictly mandatory, but it sounds very natural. Structures starting with além de set up an expectation that you are adding information. Including também (also) in the main clause completes this pairing perfectly to reinforce the idea of addition.